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The document outlines key concepts in genetics and cellular functions, covering topics such as nucleic acids, DNA and RNA structure, gene coding, protein synthesis, and cell division processes including mitosis and meiosis. It explains the roles of various nucleotides, proteins, and enzymes in cellular activities and provides a detailed look at DNA replication and the cell cycle. Additionally, it addresses heredity, genetic variation, and the basics of research methodologies in education.

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1 04 Genetics and cellular function Learning Objectives • With respect to nucleic acids: • Identify the monomers and polymers. • Compare and contrast general molecular structure. • Define the terms genetic code, transcription and translation. • Explain how and why RNA is synthesized. • Explain the roles of tRNA, mRNA, and rRNA in protein synthesis. • Define the term cellular respiration. • With respect to glycolysis, the Krebs (citric acid or TCA) cycle, and the electron transport chain: compare and contrast energy input, efficiency of energy production, oxygen use, by-products and cellular location. • Referring to a generalized cell cycle, including interphase and the stages of mitosis: • Describe the events that take place in each stage. • Identify cells that are in each stage. • Analyze the functional significance of each stage. • Distinguish between mitosis and cytokinesis.
• Describe DNA replication. • Analyze the interrelationships among chromatin, chromosomes and chromatids. • Give examples of cell types in the body that divide by mitosis and examples of circumstances in the body that require mitotic cell division. • Compare and contrast the processes of mitosis and meiosis. • Provide specific examples to demonstrate how individual cells respond to their environment (e.g., in terms of organelle function, transport processes, protein synthesis, or regulation of cell cycle) in order to maintain homeostasis in the body. • Predict factors or situations that could disrupt organelle function, transport processes, protein synthesis, or the cell cycle. • Predict the types of problems that would occur if the cells could not maintain homeostasis due to abnormalities in organelle function, transport processes, protein synthesis, or the cell cycle. 2 DNA and RNA—The Nucleic Acids DNA Structure • Deoxyribonucleic acid (DNA)—
long, thread-like molecule with 2 nm diameter, but varied length • 46 DNA molecules in nucleus of most human cells • Average length about 43,000 μm each • DNA (and other nucleic acids) are polymers of nucleotides • Nucleotide consists of a sugar, phosphate group, and nitrogenous base • A single DNA nucleotide • One deoxyribose sugar • One phosphate group • One nitrogenous base 3 Nitrogenous Bases • Purines—double ring • Adenine (A) • Guanine (G) • Pyrimidines—single ring • Cytosine (C)
• Thymine (T) • Uracil (U) (not found in DNA, only found in RNA) DNA Structure • Phosphate and Sugar unite by covalent bonds to form “backbone” • Nitrogenous bases of two backbones united by hydrogen bonds • A purine on one strand always bound to a pyrimidine on the other • A–T two hydrogen bonds • C–G three hydrogen bonds • Double helix shape of DNA (resembles spiral staircase) • Law of complementary base pairing • One strand determines base sequence of other 4 Chromatin and Chromosomes • Most human cells have 2 million μm (2m) of DNA • Nucleosome - DNA winds around eight
histone proteins (like thread around spool) • Chromatin consists - thousands of repeating nucleosomes • Occurs as 46 chromosomes in most cells • In nondividing cells, chromatin is so slender it cannot be seen with light microscope • Granular appearance under electron microscope • Chromatin thrown into complex, irregular loops and coils • 1,000 times shorter than original molecule Chromosomes • When preparing to divide, cell makes copy of all nuclear DNA • Each chromosome then consists of two parallel filaments of identical DNA - sister chromatids • Becomes visible with light microscope • Chromatids are joined at constricted centromere • Kinetochores—proteins on each side of centromere 5
RNA Structure and Function • Ribonucleic acids (RNAs) – a polymer of nucleotides that resemble DNA but • Ribose sugar instead of deoxyribose • Uracil instead of Thymine • RNA is usally single stranded and much shorter in length than DNA • Three important RNAs for protein synthesis • Messenger RNA (mRNA) • Ribosomal RNA (rRNA) • Transfer RNA (tRNA) Genes and Their Action 6 What Is a Gene? • 46 human chromosomes come in two sets of 23 chromosomes (one from each parent) • Genome—all the DNA in one 23-chromosome set • Genomics—study of the whole genome and how it affects structure and function of the whole organism • Genome is 3.1 billion nucleotides
• Humans have about 20,000 genes • Only about 2% of total DNA is genes • Other 98% is noncoding DNA that plays role in chromosome structure and gene regulation • Gene—an information-containing segment of DNA that codes for the production of a molecule of RNA that plays a role in synthesizing one or more proteins • Amino acid sequence of a protein is determined by the nucleotide sequence in the DNA The Genetic Code • Body can make millions of different proteins (the proteome), from just 20 amino acids, and encoded by genes made of just four nucleotides (A, T, C, G) • Genetic code—a system that enables these four nucleotides to code for amino acid sequences of all proteins • Minimum code to symbolize 20 amino acids is three nucleotides per amino acid • Base triplet - a sequence of three DNA nucleotides that stands for one amino acid • Codon - the 3-base sequence in mRNA
• 64 possible codons available to represent the 20 amino acids • 61 code for amino acids; 3 are stop codons • Stop codons—UAG, UGA, and UAA: signal “end of message,” like a period at the end of a sentence • Start codon—AUG codes for methionine, and begins the amino acid sequence of the protein 7 Protein Synthesis • All body cells, except sex cells and some immune cells, contain identical genes • But different genes are activated in different cells • Any given cell uses one-third to two-thirds of its genes while the rest are “dormant” • When a gene is activated, mRNA complementary to the genes is synthesized in the nucleus • Transcription • mRNA Migrates from the nucleus to cytoplasm where it codes for amino acids used to make protein • Translation
Transcription • Transcription - copying genetic instructions from DNA to mRNA • RNA polymerase - binds to certain DNA sequences that signal start (e.g., TATATA) and synthesize mRNA copy • RNA polymerase opens up the DNA helix and reads bases from one strand of DNA • RNA polymerase rewinds the DNA helix behind it so it can be transcribed again • Transcription stops to certain DNA sequences called the Terminator 8 Alternative Splicing • Transcription actually makes Pre-mRNA • Pre-mRNA has: • Intervening introns that are removed by nuclear enzymes • Exons that will form “mature” mRNA that is exported from nucleus • Alternative splicing - variations in the way exons are spliced allow for a variety of proteins to be produced from one gene • Finally cap (for ribosome binding) has to be added
Translation • Translation - process that converts the language of nucleotides into the language of amino acids • Three main participants in translation • mRNA carries code from nucleus to cytoplasm • Transfer RNA (tRNA) delivers a single amino acid to the ribosome for it to be added to growing protein chain • Contains an anticodon - series of 3 nucleotides that are complementary to codon of mRNA • Attached to the correct amino acid • Ribosomes - organelles that read the message • Found free in cytosol, on rough ER, and on nuclear envelope • Consist of large and small subunits, where each subunit is made of several enzymes and ribosomal RNA (rRNA) molecules 9 Translation - Initiation • Three steps to translation: Initiation, Elongation, Termination 1. Initiation
• Small ribosomal subunit binds to mRNA near cap and slide along until • Initiator tRNA (bearing methionine) pairs with start codon • Large ribosomal subunit joins the complex and the now fully formed ribosome begins reading bases Translation – Elongation 2. Elongation • Next tRNA (with its amino acid) binds to ribosome while its anticodon pairs with next codon of mRNA • Peptide bond forms between methionine and second amino acid • Ribosome slides to read next codon and releases initiator tRNA (empty) • Next tRNA with appropriate anticodon brings its amino acid to ribosome • Another peptide bond forms (between 2nd and 3rd amino acids) • Process continually repeats, extending peptide to a protein 10 Translation - Termination • Three steps to translation: Initiation, Elongation, Termination 3. Termination • When ribosome reaches stop codon a release factor binds to it
• Finished protein breaks away from ribosome • Ribosome dissociates into two subunits Review of Transcription and Translation 11 Protein Processing and Secretion 1 • Protein synthesis is not finished when the amino acid sequence (primary structure) has been assembled • Chaperone proteins help fold protein into precise secondary and tertiary structures for proper function • Proteins to be used in the cytosol are made on free ribosomes in the cytosol • Proteins headed for lysosomes, secretion, or integral membrane proteins are made on ribosomes on the rough ER • mRNA/ribosome migrates docks on surface of ER and feeds polypeptide to interior • Some post-translational modification (e.g. disulfide bridges, glycosylation) occurs in ER lumen • When rough ER is finished with protein • Pinches off transport vesicle coated with clathrin • Vesicles detach from ER and carry protein to the nearest cisterna of Golgi complex
Protein Processing and Secretion 2 • ER derived vesicles fuse with Golgi cisterna • Golgi complex further modifies the protein • Often adds carbohydrate chains and assembles glycoproteins • Golgi cisterna farthest from ER buds off new coated Golgi vesicles containing finished protein • Some Golgi vesicles become lysosomes • Other Golgi vesicles become secretory vesicles and migrate to plasma membrane, fuse to it, and release their cell product by exocytosis • Other Golgi vesicles migrate to plasma membrane, fuse to it, and deliver integral transmembrane proteins 12 Synthesizing Compounds Other Than Proteins • Cells synthesize glycogen, fat, steroids, phospholipids, pigments, and
other compounds • No genes for these products, but their synthesis is under indirect genetic control • They are produced by enzymatic reactions, and enzymes are proteins encoded by genes • Example: production of testosterone (a steroid) • A cell of the testes takes in cholesterol • Enzymatically converts it to testosterone • Only occurs when genes for enzyme are active DNA Replication and the Cell Cycle 13 DNA Replication • Before a cell divides, it must duplicate its DNA so it can give a complete copy of all its genes to each daughter cell • Since DNA controls all cellular function, this replication process must be very exact • Law of complementary base pairing - we can predict the base sequence of one DNA strand if we know the sequence of the other
• Four steps of DNA replication: unwinding, unzipping, building new DNA strands, repackaging 1. DNA unwinds from histones 2. DNA helicase unzips segment of double helix exposing bases • Replication fork - the point of DNA opening DNA Replication 2 • Four steps of DNA replication: unwinding, unzipping, building new DNA strands, repackaging 1. DNA polymerase builds new DNA strands • Polymerase reads exposed bases and matches complementary free nucleotides • Separate polymerase molecules work on each strand proceeding in opposite directions • DNA polymerase does make mistakes, but • Double checks the new base pair and tends to replace incorrect, biochemically unstable pairs with more stable, correct pairs • Result is only one error per 1 billion bases replicated - Mutation • Some mutations cause no ill effects, others kill the cell, turn it cancerous, or cause genetic defects in future generations 2. Newly made DNA is repackaged • With thousands of polymerase molecules working simultaneously on the DNA, all 46 chromosomes are replicated in 6 to 8
hours • Millions of histones are made in the cytoplasm while DNA is replicated and they are transported into the nucleus soon after DNA replication ends • Each new DNA helix wraps around the histones to make new nucleosomes 14 The Cell Cycle • Cell cycle—cell’s life from one division to the next • Includes interphase and mitotic phase • Interphase includes three subphases • G1, S, G2 • Mitotic phase includes multiple subphases • Prophase, Metaphase, Anaphase, Telophase Mitosis 1 • Meiosis is cell division resulting in two daughter cells (gametes) with half the genetic information • Mitosis is cell division resulting in two genetically identical
daughter cells • Functions of mitosis • Development of the individual from one fertilized egg to roughly 50 trillion cells • Growth of all tissues and organs after birth • Replacement of cells that die • Repair of damaged tissues • Four phases of mitosis • Prophase, metaphase, anaphase, telophase 15 Mitosis 2 • Prophase • Genetic material condenses into 46 compact chromosomes • Two chromatids per chromosome • Nuclear envelope disintegrates • Centrioles sprout spindle fibers (long microtubules) • Spindle fibers push centriole
pairs apart • Some spindle fibers attach to kinetochores of centromeres of chromosomes • Metaphase • Chromosomes are aligned on metaphase plate • Spindle fibers complete mitotic spindle • Shorter microtubules from centrioles complete an aster which anchors itself to inside of cell membrane Mitosis 3 • Anaphase • Enzyme cleaves two sister chromatids apart at centromere • Single-stranded daughter chromosomes migrate to each pole of the cell as motor proteins in kinetochores crawl along spindle fibers • Telophase • Chromosomes cluster on each
side of the cell • Rough ER makes new nuclear envelope around each cluster • Chromosomes uncoil to chromatin • Mitotic spindle disintegrates • Each nucleus forms nucleoli 16 Mitosis 4 • Cytokinesis—division of cytoplasm into two cells • Telophase is the end of nuclear division but overlaps cytokinesis • Achieved by myosin protein pulling on actin in the terminal web of cytoskeleton • Creates cleavage furrow around the equator of cell • Cell eventually pinches in two Chromosomes and Heredity
17 Chromosomes and Heredity • Heredity—transmission of genetic characteristics from parent to offspring • Karyotype—chart of 46 chromosomes laid out in order by size • 23 pairs—the two members of each pair are called homologous chromosomes • 1 chromosome from each pair inherited from each parent • 22 pairs called autosomes • Look alike and carry the same genes • 1 pair of sex chromosomes (X and Y) • Female has homologous pair of X chromosomes • Male has one X and one much smaller Y chromosome • Diploid (2n) —describes any cell with 23 pairs of chromosomes (somatic cells) • Haploid (n) —describes cells containing half as many chromosomes (23 unpaired) as somatic cells; that is, sperm and egg cells • Fertilization restores diploid (2n) number to the fertilized egg and the somatic cells arise from it
Genes and Alleles • Location of a particular gene on a chromosome called locus • Different forms of gene at same locus on two homologous chromosomes called alleles • Genotype - alleles an individual possesses for a particular trait • Homozygous individuals—two identical alleles for the trait • Heterozygous individuals—different alleles for that gene • Phenotype - an observable trait • An allele is expressed if it shows in the phenotype of an individual • Dominant allele (represented by capital letter) • If present, corresponding trait is usually seen in the individual • Masks effect of recessive allele • Often produces protein responsible for visible trait • Recessive allele (represented by lowercase letter) • Corresponding trait only seen when recessive allele present on both homologous chromosomes • Often codes for a nonfunctional variant of the protein • Punnett square - diagram showing possible genotype and phenotype outcomes from parents of known genotype 18 Punnett Square
• Cleft (C) is dominant to uncleft chin (c) • CC, Cc = cleft chin • cc = uncleft chin • Can two parents with cleft chin produce child with uncleft chin? Sex Linkage • Sex-linked traits—carried on X or Y chromosome, and therefore tend to be inherited by one sex more than the other • Much more common for trait to be on X, as Y as very few genes • Recessive color blindness allele on X, no gene locus for trait on Y, so color blindness more common in men (mother is carrier in illustrated example) 19 Multiple Alleles, Codominance, and Incomplete Dominance • Gene pool - genetic makeup of whole population (an individual can only have two alleles, but population can have many) • Multiple alleles—more than two allelic forms of gene
• Example: three alleles for ABO blood types • IA, IB, i alleles for ABO blood types • Codominance—both alleles equally dominant • Both are phenotypically expressed • Example: IAIB = type AB blood • Incomplete dominance • Heterozygous individual shows phenotype intermediate between traits each allele would have produced alone • Example: familial hypercholesterolemia EDU 508 – Educational Research Methods COURSE DESCRIPTION In many ways, progress and change within education and training organizations and systems is driven by research. This course enables students to choose a topic to research and guides them through the decision process of methodological approaches, research procedures and evaluation and interpretation of research results. Additionally, students learn ethical procedures and formal academic writing that can be applied to careers in education and training. INSTRUCTIONAL MATERIALS Required Resources Mertler, Craig, (2019) A. Introduction to Educational Research (2nd ed.) Thousand Oaks, CA: SAGE COURSE LEARNING OUTCOMES 1. Determine the best research methodology for a given educational research topic. 2. Conduct a literature review for a given research topic.
3. Describe ethical considerations in the research process. 4. Write an educational research proposal. 5. Interpret educational research results. COURSE TOOLS AND TUTORIALS The following tools and tutorials are resources for this course and will help you succeed at exploring research articles. They should be completed within the first week. · Complete the tutorial in the Course Tools tab in your course shell and the required quiz in Week 1 entitled “Genius Navigator” to earn your Genius Navigator Badge. WEEKLY COURSE SCHEDULE The standard requirement for a 4.5 credit hour course is for students to spend 13.5 hours in weekly work. This includes preparation, activities, and evaluation regardless of delivery mode. Week Preparation, Activities, and Evaluation 1 Preparation · Read Chapter 1: What is Educational Research · Read Chapter 2: Overview of the Educational Research Process · Read the Education Research Overview located here: http://libdatab.strayer.edu/login?url=https://search.ebscohost.co m/login.aspx?direct=true&db=e0h&AN=27170113&site=eds- live&scope=site · Watch – Video from American Educational Research Association on the importance and purpose of educational research - https://www.youtube.com/watch?v=uWOP6H5uocc · Watch – The Pursuit of Ignorance on how research is not the pursuit of knowledge, but of what we don’t know - https://www.ted.com/talks/stuart_firestein_the_pursuit_of_ignor ance#t-581382 · Complete the Course Tools and Tutorials in the online course
Activities · Course Expectations and Introductions · Throughout this course, you will complete activities that simulate research and produce a research paper. To streamline the research process, the suggested sample population for your research is your classmates. Therefore, your research topic should be related to college students. · This week, begin to think about a research topic you would like to study for this class. You must have your topic selected by the end of next week. · Discussions (15 points) Evaluation · Genius Navigator Quiz (10 points) 2 Preparation · Read Chapter 3: Identifying a Research Problem · Read Chapter 4: Ethics in Educational Research · Watch Crash Course Sociology – Sociological Research Methods: https://www.youtube.com/watch?v=QwhK-iEyXYA · This video explains how researchers form a question and a hypothesis, collect data, and analyze that data · Watch Crash Course Statistics: Henrietta Lacks, the Tuskegee Experiment, & Ethical Data Collection: https://youtu.be/CzNANZnoiRs · Read Chapter 1: The Selection of a Research Approach Activities · Discussion (15 points) Evaluation · None 3 Preparation · Read Chapter 5 Reviewing Related Research · Read Ten Simple Steps for Writing a Literature
Review by Marco Pautasso,located on the course shell. · Read the APA Flow Chart located on the course shell · Watch Crash Course Statistics: Science Journalism: https://youtu.be/ZwqOoD17_LU Activities · Discussion (15 points) Evaluation · Assignment 1: The Scavenger Hunt (100 points) 4 Preparation · Read Chapter 6: Qualitative Research Methods · Watch Crash Course Statistics Correlation Doesn’t Equal Causation: https://youtu.be/GtV-VYdNt_g Activities · Discussion (15 points) Evaluation · None 5 Preparation · Read Chapter 7: Quantitative Research Methods · Watch Crash Course Statistics: The Normal Distribution: https://youtu.be/rBjft49MAO8 Activities · Discussion (15 points) Evaluation · Assignment 2: The Literature Review (200 points) 6 Preparation · Read Chapter 10: Writing a Research Proposal · Watch Crash Course Statistics: Sampling Methods and Bias with Surveys: https://youtu.be/Rf-fIpB4D50 Activities · Discussion (15 points) Evaluation · None
7 Preparation · Read Chapter 12: Quantitative Data Collection · Read Research Starters: Inferential Statistics located in the course shell. · Watch Crash Course Statistics: Test Statistics: https://youtu.be/QZ7kgmhdIwA · Watch Crash Course Statistics: T- Tests: https://youtu.be/AGh66ZPpOSQ · Reference: T-Test with a link to an excel spreadsheet where you can calculate a T- Test: https://researchbasics.education.uconn.edu/t-test/# Activities · Discussion (15 points) Evaluation · Assignment 3: Research Paper– The Foundation (200 points) 8 Preparation · Read Chapter 13: Quantitative Data Analysis Activities · Discussion (15 points) · Post your survey tool to the Survey Tool Discussion Board (50 points) Evaluation · None 9 Preparation · Read Chapter 14: Writing a Final Research Report · Look at the Is It Plagiarism? infographic in the course shell · Watch The Punishable Perils of Plagiarism - https://www.youtube.com/watch?v=SrjoaaIxaJI Activities · Discussion (15 points) · Collect your final data and close your survey tool.
Evaluation · None 10 Preparation · Read Chapter 8: Mixed-Methods Research · Read Chapter 9: Action Research Activities · Discussion (15 points) Evaluation · Assignment 4: Research Paper – Putting it All Together (290 points) 11 Preparation · Reading(s): None Activities · Discussion Evaluation · None GRADING SCALE – GRADUATE Assignment Total Points % of Grade Genius Navigator Quiz 10 1% Assignment 1: The Scavenger Hunt 100 10% Assignment 2: Research Paper – The Literature Review 200 20% Assignment 3: Research Paper – The Foundation 200 20%
Assignment 4: Research Paper – Putting it All Together 290 29% Post Survey Tool on Survey Discussion Board 50 5% Participation (10 discussions worth 15 points each) 150 15% Totals 1,000 100% Points Percentage Grade 900 – 1,000 90% – 100% A 800 – 899 80% – 89% B 700 – 799 70% – 79% C Below 700 Below 70% F Supplemental Resources Educational Research Websites American Educational Research Journal. (2013). General format. Retrieved from http://aer.sagepub.com/
American Educational Research Association. (2013). General format. Retrieved from http://www.aera.net/ American Institutes for Research (2103). General format. Retrieved from http://www.air.org/ The Chronicle of Higher Education. (2013). General format. Retrieved from http://chronicle.com/section/Home/5 EDU 508 – Educational Research Methods © 2019 Strayer University. All Rights Reserved. This document contains Strayer University confidential and proprietary information and may not be copied, further distributed, or otherwise disclosed in whole or in part, without the expressed written permission of Strayer University. EDU 508 STUDENT GUIDE 1192 (12-03-2018) Page 2 of 16 Research Assignment Overview For the purpose of this class, you will choose a research topic and design a 3-5 question survey to study that topic. This project is designed to give you an idea of how to conduct educational research, how to interpret those results, and how those results can be used to affect teaching methods, curriculum, school policy, and educational law. The core of your research project will be your research instrument, e.g. your survey. Surveys must collect data anonymously (i.e. they don’t ask for names or other information that can be used to identify someone) and be easily accessible such as through a web link.
The following survey tools are listed in your book. You may also choose to use your own tool such as GoogleDocs to create a survey and collect data. Explore the tools below and see which one you like the best. All will require you to create an account but have free access for trial accounts and individual/limited use. · KwikSurveys (www.kwiksurveys.com) · Murvey (www.murvey.com) · Qualtrics (www.qualtrics.com) · QuestionPro (www.questionpro.com) · SurveyMonkey (www.surveymonkey.com) · Zoho Survey (www.zoho.com/survey) · Zoomerang (www.zoomerang.com) You will need to have your survey tool selected and your survey questions written no later than week 7 so you can post it in week 8. Research Study Planning Guidelines This course is designed as a series of activities and assignments that build upon each other cumulatively and result in a complete research paper. Therefore, it is important that you complete the activities and assignments in the weeks required to be able to progress forward. You are encouraged to work ahead, but at a minimum the activities should be completed in the weeks suggested below. The following checklist is provided to help you prepare for and complete the assignments in this course. Specific assignment instructions are located in the online course. The checklist does not include readings, and discussion questions. Activity
Complete Activity in Week To Support Assignment # Genius Navigator tutorial and quiz located in the online course. 1 1 through 4 Sign up for a survey account. 1-7 1 through 4 Review research related to your research topic. 1 through 7 3 Develop questions for your survey. 5-7 4 Distribute questions to your classmates via the survey discussion board. 8 4 Download data from your survey tool. 9 4 Analyze data from your survey tool and report on descriptive statistics. 10 4 Assignment 1: The Scavenger Hunt Due Week 3 and worth 100 points Let’s put your investigative skills to work! In this assignment, visit the Strayer online library located in research.strayer.com or the Resource Center tab in Blackboard and find four (4) peer- reviewed quantitative articles related to your topic. Read each article.
Write a three to five (3-5) page paper in which you: 1. Summarize each article [approximately one to two (1-2) paragraphs per article] and identify the: a. Purpose of the research. b. Problem statement. c. Gaps in literature that studied the problem. d. Research question and/or hypotheses. e. Theory or conceptual framework. f. Findings of the research. 2. Describe one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. 3. Provide a preliminary reference page in APA format of the articles you summarized. 4. Include at least four (4) peer-reviewed quantitative or qualitative articles related to your topic. Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Conduct a literature review for a given research topic. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 100
Assignment 1: The Scavenger Hunt Criteria Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Summarize each article related to research topic. Weight: 50% Did not submit or incompletely summarized each article and/or articles were not related to research topic. Partially summarized each article and/or articles were partially related to the research topic. Satisfactorily summarized each article and articles were related to the research topic. Thoroughly summarized each article and each article was related to the research topic. 2. Describe one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Weight: 30% Did not submit or incompletely described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Partially described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Satisfactorily described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Thoroughly described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. 3. Writing Mechanics, Grammar, and Formatting Weight: 10% Serious and persistent errors in grammar, spelling, punctuation, or formatting.
Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting. 4. Appropriate use of APA in-text citations and reference section Weight: 10% Lack of in-text citations and / or lack of reference section. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. Assignment 2: Research Paper – The Literature Review Due Week 5 and worth 200 points For this assignment, you will create the second part of your research paper. The literature review should consist of a total of seven to ten (7-10) articles related to your research topic. These articles may include any articles you have previously found throughout this course. You should use the headings below for the sections of your paper. Write a three to five (3-5) page paper in which you: 1. Identify two to three (2-3) common themes in the literature. 2. Contrast the findings and results of the literature. 3. Identify gaps in the literature. 4. Summarize the literature as it relates to your topic. 5. Include seven to ten (7-10) peer-reviewed quantitative or qualitative articles related to your topic.
Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Conduct a literature review for a given research topic. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 200 Assignment 3: Research Paper Part 2 – The Literature Review Criteria Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Identify two to three (2-3) common themes in the literature. Weight: 20% Did not submit or incompletely identified two to three (2-3) common themes in the literature. Partially identified two to three (2-3) common themes in the literature.
Satisfactorily identified two to three (2-3) common themes in the literature. Thoroughly identified two to three (2-3) common themes in the literature. 2. Contrast the findings and results of the literature. Weight: 20% Did not submit or incompletely contrasted the findings and results of the literature. Partially contrasted the findings and results of the literature. Satisfactorily contrasted the findings and results of the literature. Thoroughly contrasted the findings and results of the literature. 3. Identify gaps in the literature. Weight: 20% Did not submit or incompletely identified gaps in the literature. Partially identified gaps in the literature. Satisfactorily identified gaps in the literature. Thoroughly identified gaps in the literature. 4. Summarize the literature as it relates to your topic. Weight: 10% Did not submit or incompletely summarized the literature as it relates to your topic. Partially summarized the literature as it relates to your topic. Satisfactorily summarized the literature as it relates to your topic. Thoroughly summarized the literature as it relates to your topic. 5. Writing Mechanics, Grammar, and Formatting Weight: 10% Serious and persistent errors in grammar, spelling, punctuation, or formatting. Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting.
6. 7-10 articles with appropriate use of APA in-text citations and reference section Weight: 10% Lack of in-text citations, lack of reference section and/or insufficient number of articles. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. Assignment 3: Research Paper – The Foundation Due Week 7 and worth 200 points If you have ever asked a question, wondered why something is as it is, or tried to understand an event, you have engaged in research. For this assignment, you will create the first part of your research paper. You should use the headings below for the sections of your paper. You will craft the framework of your research using the articles you collected and summarized from Assignment 1 and / or other articles you found that relate to your research topic. Assignments 2, 3, and 4 will all build on each other to create one comprehensive research paper. Each time you submit an assignment, your instructor will provide feedback that you can use moving forward with the other parts of the research paper. Write a four to five (7-10) page paper in which you: 1. Introduction Section - Describe the: a. Introduction to your topic. b. Purpose of your research.
c. Problem statement. 2. Literature Review - Summarize the literature you collected related to your topic. (This will mainly be from Assignment 2.) 3. Research Question - Identify the: a. Gap(s) in the literature. b. Research question or hypotheses of your topic. c. Proposed theory for your research. 4. Include at least six (6) peer-reviewed articles related to your topic. Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Determine the best research methodology for a given educational research topic. · Conduct a literature review for a given research topic. · Describe ethical considerations in the research process. · Write an educational research proposal. · Interpret educational research results. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 200 Assignment 2: Research Paper Part 1 – The Foundation Criteria
Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Wrote a complete introduction. Weight: 40% Did not submit or incompletely wrote an introduction. Partially wrote an introduction. Satisfactorily wrote an introduction. Thoroughly wrote an introduction. 2. Summarize the literature you collected related to your topic. Weight: 15% Did not submit or incompletely summarized the literature you collected related to your topic. Partially summarized the literature you collected related to your topic. Satisfactorily summarized the literature you collected related to your topic. Thoroughly summarized the literature you collected related to your topic. 3. Research question section is organized and addresses the gaps in the literature. Weight: 25% Did not submit or incompletely wrote the research question section that is organized and addresses the gaps in the literature. Partially identified wrote the research question section that is organized and addresses the gaps in the literature. Satisfactorily wrote the research question section that is organized and addresses the gaps in the literature. Thoroughly wrote the research question section that is organized and addresses the gaps in the literature.
4. Writing Mechanics, Grammar, and Formatting Weight: 10% Serious and persistent errors in grammar, spelling, punctuation, or formatting. Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting. 5. Appropriate use of APA in-text citations, number of quality sources, and reference section Weight: 10% Lack of in-text citations, number of quality sources, and / or lack of reference section. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. Assignment 4: Research Paper: Putting it All Together Due Week 10 and worth 290 points What do reporters, crime scene investigators, and sports broadcasters have in common? All of these occupations are focused on reporting the results from data or information. The final part of your research paper is about the data procedures, reporting, and interpretation of the results of your research topic. For this assignment, you will create the last part of your research paper. Build on your paper from Assignments 2 and 3, and integrate feedback from your instructor. You should use the
headings below for the sections of your paper. Write a twelve to fifteen (12-15) page paper (this includes the work you already completed in Assignments 2 and 3) in which you: These items you should have already completed in Assignments 2 and 3: 1. Describe the: a. Introduction to your topic. b. Purpose of your research. c. Problem statement. 2. Summarize the literature you collected related to your topic. 3. Identify the: a. Gap(s) in the literature. b. Research question or hypotheses of your topic. c. Proposed theory for your research. 4. Identify two to three (2-3) common themes in the literature. 5. Contrast the findings and results of the literature. 6. Include seven to ten (7-10) peer-reviewed quantitative or qualitative articles related to your topic. These items are new for Assignment 4: 1. Describe the participants in the study. 2. Methodology a. Describe the research instrument participants completed in the study. b. Explain the procedures that you conducted. 3. Perform the data analysis. 4. Interpret Results a. Summarize your findings. b. Interpret the results of the data analysis. c. Describe the limitations of your research. 5. Write a conclusion where you pose additional research questions that can be studied from your research.
Remember to address the feedback from your instructor for Assignments 2 and 3. Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Determine the best research methodology for a given educational research topic. · Conduct a literature review for a given research topic. · Describe ethical considerations in the research process. · Write an educational research proposal. · Interpret educational research results. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 290 Assignment 4: Research Paper – Putting it All Together Criteria Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Included material from assignments 1-3.
Weight: 2% Did not submit or incompletely included material from assignments 1-3. Partially included material from assignments 1-3. Satisfactorily included material from assignments 1-3. Thoroughly included material from assignments 1-3. 7. Describe the participants in the study. Weight: 10% Did not submit or incompletely described the participants in the study. Partially described the participants in the study. Satisfactorily described the participants in the study. Thoroughly described the participants in the study. 8. Describe the instrument participants completed in the study Weight: 10% Did not submit or incompletely described the instrument participants completed in the study. Partially described the instrument participants completed in the study. Satisfactorily described the instrument participants completed in the study. Thoroughly described the instrument participants completed in the study. 9. Explain the procedures that you conducted. Weight: 10% Did not submit or incompletely explained the procedures that you conducted. Partially explained the procedures that you conducted. Satisfactorily explained the procedures that you conducted. Thoroughly explained the procedures that you conducted. 10. Perform the data analysis. Weight: 10% Did not submit or incompletely performed the data analysis. Partially performed the data analysis. Satisfactorily performed the data analysis. Thoroughly performed the data analysis.
11. Summarize your findings. Weight: 5% Did not submit or incompletely summarized your findings. Partially summarized your findings. Satisfactorily summarized your findings. Thoroughly summarized your findings. 12. Interpret the results of the data analysis. Weight: 5% Did not submit or incompletely interpreted the results of the data analysis. Partially interpreted the results of the data analysis. Satisfactorily interpreted the results of the data analysis. Thoroughly interpreted the results of the data analysis. 13. Summarize the findings and limitations of your research. Weight: 5% Did not submit or incompletely summarized the findings and limitations of your research. Partially summarized the findings and limitations of your research. Satisfactorily summarized the findings and limitations of your research. Thoroughly summarized the findings and limitations of your research. 15. Writing Mechanics, Grammar, and Formatting Weight: 5% Serious and persistent errors in grammar, spelling, punctuation, or formatting. Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting. 16. Appropriate use of APA in-text citations and reference section Weight: 5%
Lack of in-text citations and / or lack of reference section. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. 17. Information Literacy / Integration of Sources Weight: 5% Serious errors in the integration of sources, such as intentional or accidental plagiarism, or failure to use in-text citations. Sources are partially integrated using effective techniques of quoting, paraphrasing, and summarizing. Sources are mostly integrated using effective techniques of quoting, paraphrasing, and summarizing. Sources are consistently integrated using effective techniques of quoting, paraphrasing, and summarizing. The specific course learning outcomes associated with this assignment are: · Determine the best research methodology for a given educational research topic. · Conduct a literature review for a given research topic. · Describe ethical considerations in the research process. · Write an educational research proposal. · Interpret educational research results. Assignment 2: Research Paper – The Literature Review
Due Week 5 and worth 200 points See the assignment overview here. For this assignment, you will create the second part of your research paper. The literature review should consist of a total of seven to ten (7-10) articles related to your research topic. These articles may include any articles you have previously found throughout this course. You should use the headings below for the sections of your paper. Write a three to five (3-5) page paper in which you: 1. Identify two to three (2-3) common themes in the literature. 2. Contrast the findings and results of the literature. 3. Identify gaps in the literature. 4. Summarize the literature as it relates to your topic. 5. Include seven to ten (7-10) peer-reviewed quantitative or qualitative articles related to your topic. Your assignment must follow these formatting requirements: • Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. • Include a cover page containing the title of the assignment, the student’s
name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: • Conduct a literature review for a given research topic. 1 05 Histology Expected Learning Outcomes • Define the term histology. • List the four major tissue types. • Contrast the general features of the four major tissue types. • Classify the different types of epithelial tissues based on distinguishing structural characteristics. • Describe locations in the body where each type of epithelial tissue can be found. • Describe the functions of each type of epithelial tissue in the human body and correlate function with structure for each tissue type.
• Classify the different types of connective tissues based on distinguishing structural characteristics • Describe locations in the body where each type of connective tissue can be found. • Describe functions of each type of connective tissue in the human body and correlate function with structure for each tissue type. • Compare and contrast the roles of individual cell types and fiber types within connective tissue. • Classify the different types of muscle tissues based on distinguishing structural characteristics and location in the body. • Describe functions of each type of muscle tissue in the human body and correlate function with structure for each tissue type. • Describe locations in the body where nervous tissue can be found. • Describe the structure and function of neurons and neuroglial cells in nervous tissue • Describe the structure and function of mucous, serous, and cutaneous membranes. • Describe locations in the body where each type of membrane can be found. • Distinguish between exocrine and endocrine glands, structurally and functionally.
• Identify example locations in the body of exocrine and endocrine glands. • Classify the different kinds of exocrine glands based on structure and function. 2 Introduction • There are 50 trillion cells of 200 different cell types • Four broad categories of tissues • Epithelial tissue • Connective tissue • Nervous tissue • Muscular tissue • Histology (microscopic anatomy) - the study of tissues and how they are arranged into organs • Organ - structure with discrete boundaries that is composed of two or more tissue types The Study of Tissues 3
The Primary Tissue Classes • Tissue - a group of similar cells and cell products working together to perform a specific role in an organ • The four primary tissues (epithelial, connective, nervous, and muscular) differ from each other in: • Types and functions of their cells • Characteristics of the matrix (extracellular material) • Relative amount of space occupied by cells versus matrix • Matrix (extracellular material) is composed of: • Fibrous proteins • Clear gel called ground substance • Also known as tissue fluid, extracellular fluid (ECF), interstitial fluid Interpreting Tissue Sections • Histologists preserve (fix), slice into thin sections one or two cells thick, and artificially colored with histological stains tissues • Some stains bind to different cellular components • Leads to ‘artifacts’ • Cell may be larger or smaller • Nucleus may be missing • Ducts might not look continuous 4
Interpreting Tissue Sections • Longitudinal section (l.s.) • Tissue cut on its long axis • Cross section (c.s. or x.s.) or transverse section (t.s.) • Tissue cut perpendicular to long axis of organ • Oblique section • Tissue cut at angle between cross and longitudinal sections Epithelial Tissue 5 Epithelial Tissue • Epithelia are sheets of closely adhering cells, one or more cells thick • Covers body surfaces, lines body cavities, makes most glands • Functions vary • Protect deeper tissues from injury and infection • Produce and release chemical secretions • Excrete wastes • Absorb chemicals including nutrients • Selectively filter substances • Sense stimuli
• Avascular (does not have blood vessels) • Usually nourished by underlying connective tissue • Between an epithelium and underlying connective tissue is Basement Membrane • Collagen, reticular proteins, glycoproteins, other protein- carbohydrate complexes that anchors to connective tissue below • Apical surface - surface of epithelial cell that faces away from the basement membrane • Basal surface - surface of epithelial cell facing the basement membrane • Cells closest to connective tissue usually have a high rate of mitosis Cell Shapes in Epithelial Tissue • Simple epithelia contain one layer of cells • Named by shape of cells • All cells touch basement membrane • Stratified epithelia contain more than one layer • Named by shape of apical cells • Some cells rest on top of others and do not touch basement membrane 6
Simple Squamous Epithelium • Single row of thin cells • Locations: air sacs of lungs, some kidney tubules, lining of heart and blood vessels (endothelium), and serosa • Functions: Permits rapid diffusion or transport of substances, secretes serous fluid a: © McGraw-Hill Education/Dennis Strete, photographer Simple Cuboidal Epithelium • Single layer of square or round cells • Locations: Liver, thyroid, some glands, bronchioles, and most kidney tubules • Functions: Absorption and secretion of substances, mucus production 7 Simple Columnar Epithelium • Single row of tall, narrow cells with oval nuclei in basal half of cell • Often have microvilli (brush border) • Ciliated in some organs
• May possess goblet cells • Locations: Lining of GI tract, uterus, kidney, and uterine tubes • Functions: Absorption and secretion of substances, mucus production Pseudostratified Epithelium • Looks multilayered, but all cells touch basement membrane • Nuclei at several layers • Often has cilia and goblet cells • Locations: Respiratory tract and portions of male urethra • Functions: Secretes and propels mucus 8 Keratinized Stratified Squamous Epithelium • Multiple cell layers; cells become flat and scaly toward surface • Locations: epidermis; palms and soles very heavily keratinized • Functions: Resists abrasion; retards water loss through skin; resists penetration by pathogenic organisms Non-keratinized Stratified Squamous Epithelium
• Same as keratinized epithelium without surface layer of dead cells • Locations: Tongue, oral mucosa, esophagus, and vagina • Functions: Resists abrasion and penetration of pathogens 9 Stratified Cuboidal Epithelium • Two or more cell layers; surface cells square or round • Locations: Sweat gland ducts, ovarian follicles, and seminiferous tubules • Functions: Secretes sweat, produces sperm, produces ovarian hormones Transitional Epithelium • Multilayered epithelium with surface cells that change from round to flat when stretched • Locations: ureter and bladder • Functions: Allows for filling of urinary tract 10
Connective Tissue Connective Tissue: Overview • Diverse, abundant type of tissue in which cells occupy less space than matrix • Supports, connects, and protects organs • Highly variable vascularity • Loose connective tissues have many blood vessels • Cartilage has few or no blood vessels • Functions of connective tissues vary • Connecting organs - tendons and ligaments • Support - bones and cartilage • Physical protection - bone • Immune protection - white blood cells attack foreign invaders • Movement - bones provide lever system • Storage - fat, calcium, phosphorus • Heat production - brown fat in infants • Transport – blood • Four categories: Fibrous, adipose, supportive, and fluid 11 1 - Fibrous Connective Tissue • Compos of Cells, Fibers, and Ground substance 1. Cells • Fibroblasts produce fibers and ground substance of matrix • Macrophages (from monocytes) phagocytize foreign
material and activate immune system when they sense foreign matter (antigens) • Leukocytes (WBCs) • Neutrophils attack bacteria • Lymphocytes react against bacteria, toxins, and other foreign agents • Plasma cells (from lymphocytes) synthesize antibodies • Mast cells often found alongside blood vessels • Secrete heparin to inhibit clotting • Secrete histamine to dilate blood vessels • Adipocytes store triglycerides 1 - Fibrous Connective Tissue 2. Fibers • Collagenous fibers • Tough, flexible, and stretch-resisant • Tendons, ligaments, and deep layer of the skin are mostly collagen • Less visible in matrix of cartilage and bone • Reticular fibers • Thin collagen fibers coated with glycoprotein that form framework of spleen and lymph nodes as well as basement membrane • Elastic fibers • Thin, branching
• Made of protein called elastin • Allows stretch and recoil 3. Ground Substance • Glycosaminoglycans (GAGs) • Long polysaccharides composed of amino sugars and uronic acid (disaccharides) • Regulate water and electrolyte balance of tissues • Chondroitin sulfate—most abundant GAG • Responsible for stiffness of cartilage • Other examples: heparin and hyaluronic acid • Proteoglycans • Gigantic molecules (core protein plus GAGs) shaped like bottle brushes • Form gravy-like colloids that hold tissues together • Adhesive glycoproteins • Protein-carbohydrate complexes • Bind components of a tissue together 12 Types of Fibrous Connective Tissue • Loose connective tissue • Much gel-like ground substance between cells • Types • Areolar
• Reticular • Dense connective tissue • Fibers fill spaces between cells • Types vary in fiber orientation • Dense regular connective tissue • Dense irregular connective tissue Loose Connective Tissue: Areolar • Lots of seemingly empty space is ground substance • Possess all six cell types (Fibroblasts, Macrophages, Neutrophils, Lymphocytes, Plasma cells, Mast cells, and Adipocytes) • Fibers run in random directions • Mostly collagenous, but elastic and reticular also present • Found in tissue sections from almost every part of the body, surrounds blood vessels and nerves • Nearly every epithelium rests on a layer of areolar tissue • Blood vessels provide nutrition to epithelium and waste removal • Ready supply of infection-fighting leukocytes that move about freely in areolar tissue 13 Loose Connective Tissue: Reticular Tissue
• Mesh of reticular fibers and fibroblasts • Found in lymph nodes, spleen, thymus, and bone marrow • Forms supportive stroma (framework) for lymphatic organs Dense Regular Connective Tissue • Densely packed, parallel collagen fibers • Only cell type is fibroblast with compressed nuclei • Found in tendons (attach muscles to bones) and ligaments (attach bones to bones) • Some ligaments have extra elastic fibers (elastic tissue) 14 Dense Irregular Connective Tissue • Densely packed, randomly arranged, collagen fibers and few visible cells • Withstands unpredictable stresses • Locations: deeper layer of skin; capsules around organs 2 - Adipose Tissue • Adipocytes are dominant cell type • Space between adipocytes is occupied by areolar tissue, reticular tissue, and blood capillaries
• Adipose tissue is the body’s primary energy reservoir • Empty-looking cells due to large central globule of triglycerides • Nucleus pressed against cell membrane • Functions: Energy storage, insulation, cushioning • Brown fat of infants, children, and juveniles produces heat 15 3 - Supportive Connective Tissue: Cartilage • Stiff connective tissue with flexible matrix • Matrix rich in glycosaminoglycans and collagen fibers • Cells • Chondroblasts - cartilage cells that produce the matrix that will trap them • Chondrocytes - cartilage cells that are trapped in lacunae (cavities) • No blood vessels • Diffusion brings nutrients and removes wastes (thus heals slowly) • Wrapped with sheath of dense irregular connective tissue (perichondrium) with reserved chondroblasts • Except articular cartilage and fibrocartilage • Three types of cartilage
• Hyaline cartilage, fibrocartilage, and elastic cartilage Hyaline Cartilage • Clear, glassy appearance because of fineness of collagen fibers • Eases joint movement, holds airway open, moves vocal cords, growth of juvenile long bones • Locations: Articular cartilage, costal cartilage, trachea, larynx, fetal skeleton 16 Elastic Cartilage • Cartilage containing abundance of elastic fibers • Provides flexible, elastic support • Locations: external ear and epiglottis Fibrocartilage • Cartilage containing large, coarse bundles of collagen fibers • Resists compression and absorbs shock
• Lacks perichondrium • Locations: pubic symphysis, menisci, and intervertebral discs 17 3 - Supportive Connective Tissue: Bone • Bone (osseous) tissue is a calcified connective tissue • Bones of the skeleton are organs (made of bone tissue, cartilage tissue, marrow, and other tissue types) • Wrapped with periosteum (dense irregular connective tissue) • Osteocytes - mature bone cells within lacunae • Two forms of osseous tissue • Spongy bone: porous appearance • Delicate struts of bone (trabeculae) covered by compact bone • Found in heads of long bones and in middle of flat bones such as the sternum • Compact bone: denser, with no visible spaces • Arranged in cylinders that surround central (haversian) canals that run longitudinally through shafts of long bones • Blood vessels and nerves travel through central canal • Bone matrix deposited in concentric lamellae around each central canal • Osteon - central canal and its surrounding lamellae • Delicate canals (canaliculi) allow osteocytes in lacunae to
contact each other 4 – Fluid Connective Tissue: Blood • Transports cells and dissolved matter from place to place • Plasma - blood’s ground substance • Formed elements - cells and cell fragments • Erythrocytes - red blood cells (RBCs): transport O2 and CO2 • Leukocytes - white blood cells (WBCs): defend against infection and disease • Neutrophils, eosinophils, basophils, lymphocytes, monocytes • Platelets - cell fragments involved in clotting 18 Nervous and Muscular Tissues - Excitable Tissues Nervous and Muscular Tissues—Excitable Tissues • Excitability - ability to respond to stimuli by changing membrane potential • Membrane potential - electrical charge difference (voltage) that occurs across the cell membrane • Developed to highest degree in nervous and muscular tissues • In nerve cells: changes in voltage result in rapid transmission of signals to other cells
• In muscle cells: changes in voltage result in contraction, shortening of the cell 19 Nervous Tissue • Consists of neurons (nerve cells) • Detect stimuli • Respond quickly • Transmit coded information rapidly to other cells • Neuroglia (glial) • More numerous than neurons • Neuron parts • Neurosoma (cell body) • Houses nucleus and other organelles • Dendrites • Multiple short, branched processes • Receive signals from other cells • Transmit messages to neurosoma • Axon (nerve fiber) • Sends outgoing signals to other cells
• Can be more than a meter long Muscular Tissue • Muscular tissue—elongated cells that are specialized to contract in response to stimulation • Primary job is to exert physical force on other tissues and organs • Creates movements involved in body and limb movement, digestion, waste elimination, breathing, speech, and blood circulation • Important source of body heat • Three types of muscle: skeletal, cardiac, and smooth 20 1 - Skeletal Muscle Tissue • Made of muscle fibers long thin cells • Most skeletal muscles attach to bone • Contains multiple nuclei adjacent to plasma membrane • Striations - alternating dark and light bands • Voluntary - conscious control over skeletal muscles Cardiac Muscle Tissue
• Found only in wall of heart • Cardiomyocytes are branched, shorter than skeletal muscle fibers • Contain one centrally located nucleus • Intercalated discs join cardiomyocytes end to end • Provide electrical and mechanical connection • Striated and involuntary (not under conscious control) 21 Smooth Muscle Tissue • Made of fusiform myocytes lacking striations • Cells are relatively short and have one central nucleus • Involuntary function • Most is visceral muscle - making up parts of walls of hollow organs Cell Junctions, Glands, and Membranes 22 Cell Junctions • Most cells are
anchored to each other or their matrix • Connections between cells - Cell Junctions • Four main types of cell junctions 1. Tight junctions 2. Desmosome 3. Hemidesmosome 4. Gap junction Tight Junctions • Tight junction—linkage between two adjacent cells by transmembrane cell-adhesion proteins • In epithelia, they form a zone that completely encircles each cell near its apical pole • Seals off intercellular space, making it difficult for substance to pass between cells 23 Desmosomes and Hemidesmosomes
• Hook-like, J-shaped proteins arise from cytoskeleton • Anchor cytoskeleton to membrane plaque • Transmembrane proteins from each cell joined by cell adhesion proteins • Keeps cells from pulling apart—resist mechanical stress • Hemidesmosomes - half desmosomes that anchor basal cells of an epithelium to underlying basement membrane • Epithelium cannot easily peel away from underlying tissues Gap Junctions • Gap (communicating) junction formed by connexon proteins • Connexon form ring in membrane surrounding water filled pore • Located in cardiac and smooth muscle to allow ions to pass • Not found in skeletal muscle • Located in lens and cornea to allow nutrients to pass 24 Glands • Gland - cell or organ that secretes substances for use elsewhere in the body or releases them for elimination from the body
• Usually composed of epithelial tissue in a connective tissue framework and capsule • Classified as • Exocrine glands - maintain their contact with surface of epithelium by way of a duct • Surfaces can be external (examples: sweat, tear glands) or internal (examples: pancreas, salivary glands) • Endocrine glands - have no ducts; secrete hormones directly into blood • Hormones: chemical messengers that stimulate cells elsewhere in the body • Examples: thyroid, adrenal, and pituitary glands • Some organs have both endocrine and exocrine functions • Examples: liver, gonads, pancreas • Unicellular glands – Secretory cell found in an epithelium that is predominantly nonsecretory • Can be exocrine or endocrine • Examples: mucus-secreting goblet cells in trachea or endocrine cells of stomach Exocrine Gland Structure
• Capsule - connective tissue covering of exocrine gland • Septa or trabeculae: extensions of capsule that divide interior of gland into compartments (lobes and lobules) • Stroma—connective tissue framework of the gland • Supports and organizes glandular tissue • Parenchyma—cells that perform the tasks of synthesis and secretion • Typically cuboidal or simple columnar epithelium 25 Classification of Exocrine Glands by Structure • Duct shape: simple (unbranched) vs. compound (branched) • Gland shape • Tubular: narrow secretory portion • Acinar: secretory cells form dilated sac (acinus or alveolus) • Tubuloacinar: both tubular and acinar portions Classification of Exocrine Glands by Types of Secretions • Serous glands • Produce thin, watery secretions • Perspiration, milk, tears, digestive juices
• Mucous glands • Produce glycoprotein, mucin, which absorbs water to form mucus • Goblet cells: unicellular mucous glands • Mixed glands • Contain both serous and mucous cell types and produce a mixture of the two types of secretions • Salivary glands produce this watery saliva for food digestion or thick saliva for protection 26 Classification of Exocrine Glands by Modes of Secretion • Merocrine secretion (used by eccrine glands) uses vesicles that release their secretion by exocytosis • Examples: tear glands, pancreas, gastric glands, and others • Apocrine secretion - lipid droplet covered by membrane and cytoplasm buds from cell surface • Mode of milk fat secretion by mammary gland cells • Note Apocrine sweat glands (in axillary region) are misnamed: use merocrine secretion
• Holocrine secretion - cells accumulate a product until they disintegrate • Secrete a mixture of cell fragments and synthesized substances • Examples: oil glands of skin Membranes • Membranes may be only epithelial, only connective, or a mix of epithelial, connective, and muscular tissues • Examples of membranes of only connective tissue: dura mater, synovial membranes, periosteum • Examples of membranes of only epithelium: anterior surfaces of cornea and lens of eye • Cutaneous membrane (the skin)—largest membrane in the body • Stratified squamous epithelium (epidermis) resting on a layer of connective tissue (dermis) • Relatively dry layer serves protective function 27 Mucous and Serous Membranes • Mucous membrane (mucosa) lines passages that open to the external environment • Sublayers: epithelium, lamina
propria (areolar tissue), muscularis mucosa (smooth muscle) • Absorptive, secretory, and protective functions • Often have mucus producing goblet cells • Serous membrane (serosa)— internal membrane • Simple squamous epithelium resting on a layer of areolar tissue • Produces serous fluid that arises from blood • Covers organs and lines walls of body cavities • Endothelium lines blood vessels and heart • Mesothelium lines body cavities (pericardium, peritoneum, and pleura) 1 3 Cellular form and function Expected Learning Outcomes • Identify the three main parts of a cell, and list the general
functions of each. • Explain how cytoplasm and cytosol are different. • Describe how lipids are distributed in a cell membrane, and explain their functions. • Describe how carbohydrates are distributed in a cell membrane, and explain their functions. • Describe how proteins are distributed in a cell membrane, and explain their functions. • With respect to the following membrane transport processes – simple diffusion, facilitated diffusion, osmosis, active transport, exocytosis, endocytosis, phagocytosis, pinocytosis, & filtration: • State the type of material moving in each process. • Describe the mechanism by which movement of material occurs in each process. • Discuss the energy requirements and, if applicable, the sources of energy for each process. • Give examples of each process in the human body. • Describe the effects of hypertonic, isotonic, and hypotonic conditions on cells. • Demonstrate various cell transport processes and, given appropriate information, predict the outcomes of these demonstrations. • Define the term organelle. • For each different type of organelle associated with human
cells: • Identify the organelle. • Describe the structure of the organelle. • Describe the function of the organelle 2 Introduction • All organisms are composed of cells • Cells are responsible for all structural and functional properties of a living organism • Important for understanding • Workings of human body • Mechanisms of disease Development of the Cell Theory • Cytology—scientific study of cells • Began when Robert Hooke coined the word cellulae to describe empty cell walls of cork in 17th century • Theodor Schwann concluded, about two centuries later, that all animals are made of cells • Louis Pasteur demonstrated in 1859 that “cells arise only from other
cells” • Refuted idea of spontaneous generation—living things arising from nonliving matter • Cell theory • All organisms composed of cells and cell products • Cell is the simplest structural and functional unit of life • An organism’s structure and functions are due to activities of cells • Cells come only from preexisting cells • Cells of all species exhibit biochemical similarities 3 Cell Shapes and Sizes • About 200 types of cells in human body with varied shapes • Squamous—thin, flat, scaly • Cuboidal—squarish-looking • Columnar—taller than wide • Polygonal—irregularly angular shapes, multiple sides • Stellate—star-like • Spheroid to ovoid—round to oval
• Discoid—disc-shaped • Fusiform—thick in middle, tapered toward the ends • Fibrous—thread-like • Note: A cell’s shape can appear different if viewed in a different type of section (longitudinal vs. cross section) The Relationship Between Cell Surface Area and Volume • Most cells about 10–15 micrometers (μm) in diameter • Egg cells (very large) 100 μm diameter • Some nerve cells over 1 meter long • Limit on cell size: an overly large cell cannot support itself, may rupture • For a given increase in diameter, volume increases more than surface area • Volume proportional to cube of diameter • Surface area proportional to square of diameter Large cell Diameter = 20 μm Surface area = 20 μm × 20 μm × 6 = 2,400 μm2 Volume = 20 μm × 20 μm × 20 μm = 8,000 μm3
Small cell Diameter = 10 μm Surface area = 10 μm × 10 μm × 6 = 600 μm2 Volume = 10 μm × 10 μm × 10 μm = 1,000 μm3 Effect of cell growth: Diameter (D) increased by a factor of 2 Surface area increased by a factor of 4 (= �2) Volume increased by a factor of 8 (= �3) 4 Basic Components of a Cell • Plasma (cell) membrane • Surrounds cell, defines boundaries • Made of proteins and lipids • Cytoplasm • Organelles • Cytoskeleton • Inclusions • Cytosol (intracellular fluid, ICF) • Extracellular fluid (ECF) • Fluid outside of cells
includes tissue (interstitial) fluid The Plasma Membrane • Has intracellular and extracellular faces • Functions • Defines cell boundaries • Governs interactions with other cells • Controls passage of materials in and out of cell • 98% of membrane molecules are lipids • 75% phospholipids • Amphipatic molecules arranged in a bilayer • Hydrophilic phosphate heads face water on each side of membrane • Hydrophobic tails—are directed toward the center, avoiding water • Drift laterally, keeping membrane fluid • 20% Cholesterol • Can both holds phospholipids still and stiffen membrane or prevent close packing and make membrane more flexible
• 5% Glycolipids • Phospholipids with short carbohydrate chains on extracellular face • Contributes to glycocalyx—carbohydrate coating on cell surface 5 The Plasma Membrane • 2% of the molecules but 50% of the weight of membrane are protein • Integral proteins—penetrate membrane • Transmembrane proteins pass completely through • Hydrophilic regions contact cytoplasm, extracellular fluid • Hydrophobic regions pass through lipid of the membrane • Some drift in membrane; others are anchored to cytoskeleton • Peripheral proteins
• Adhere to one face of the membrane (do not penetrate it) • Usually tethered to the cytoskeleton Some Functions of Membrane Proteins 6 The Glycocalyx • Fuzzy coat external to plasma membrane • Carbohydrate moieties of glycoproteins and glycolipids • Unique in everyone but identical twins • Functions • Physical Protection • Self Identification (e.g. in immunity or transplant compatibly) • Cell adhesion Extensions of Cell Surface: Microvilli
• Extensions of membrane (1–2 μm) • Gives 15 to 40 times more surface area • Best developed in cells specialized in absorption • On some absorptive cells they are very dense and appear as a fringe— “brush border” 7 Extensions of Cell Surface: Cilia • Cilia—hairlike processes 7–10 μm long • Single, nonmotile primary cilium found on several cells such as • Balance cells in inner ear • Motile cilia—respiratory tract, uterine tubes, ventricles of brain, ducts of testes • 50 to 200 on each cell • Beat in waves sweeping material across a surface in one direction • Power strokes followed by recovery strokes Extensions of Cell Surface: Cilia
• Axoneme—core of motile cilium • Has 9 + 2 structure of microtubules • “Grows” from basal body • Uses energy from ATP 8 Extensions of Cell Surface: Flagella and Pseudopod • Tail of a sperm—only functional flagellum in humans • Whip-like structure with axoneme identical to cilium’s • Much longer than cilium • Movement is undulating, snake-like, corkscrew • No power stroke and recovery strokes • Pseudopods—continually changing extensions of the cell that vary in shape and size • Can be used for cellular locomotion, capturing • foreign particles Membrane Transport
9 Membrane Transport • Plasma membrane is selectively permeable—allowing some things through, but preventing others from passing • Passive mechanisms require no ATP • Random molecular motion of particles provides necessary energy • Filtration, diffusion, osmosis • Active mechanisms consume ATP • Active transport and vesicular transport • Carrier-mediated mechanisms use a membrane protein to transport substances across membrane Filtration • Filtration—particles are driven through membrane by physical pressure • Examples • Filtration of water and small solutes through gaps in capillary walls • Allows delivery of water
and nutrients to tissues • Allows removal of waste from capillaries in kidneys 10 Simple Diffusion • Simple diffusion—net movement of particles from place of high concentration to place of lower concentration • Due to constant, spontaneous molecular motion • Molecules collide and bounce off each other • Substances diffuse down their concentration gradient • Does not require a membrane • Substance can diffuse through a membrane if the membrane is permeable to the substance • Factors affecting diffusion rate through a membrane • Molecular weight: larger molecules move slower • Osmosis • Osmosis—net flow of water through a selectively permeable membrane
• Water moves from the side where it (water) is more concentrated to the side where it is less concentrated • Solute particles that cannot pass through the membrane “draw” water from the other side • Water can diffuse through phospholipid bilayers, but osmosis is enhanced by aquaporins—channel proteins in membrane specialized for water passage • Cells can speed osmosis by installing more aquaporins • Osmotic pressure—hydrostatic pressure required to stop osmosis • Increases as amount of nonpermeating solute rises • Reverse osmosis—process of applying mechanical pressure to override osmotic pressure • Allows purification of water (a) Start (b) 30 minutes later 11
Osmolarity and Tonicity • One osmole (osm) = 1 mole of dissolved particles • Takes into account whether solute ionizes in water • 1 M glucose is 1 osm/L • 1 M NaCl is 2 osm/L • Osmolarity—number of osmoles per liter of solution • Body fluids contain a mix of many chemicals, and osmolarity is the total osmotic concentration of all solutes • Blood plasma, tissue fluid, and intracellular fluid are 300 milliosmoles per liter (mOsm/L) • Tonicity—ability of a surrounding solution to affect fluid volume and pressure in a cell • Depends on concentration of nonpermeating solutes • Hypotonic solution • Hypertonic solution • Isotonic solution (a) Start
(b) 30 minutes later Effects of Tonicity on RBCs • Hypotonic solution—causes cell to absorb water and swell • Has a lower concentration of nonpermeating solutes than intracellular fluid (ICF) • Distilled water is an extreme example • Hypertonic solution—causes cell to lose water and shrivel (crenate) • Has a higher concentration of nonpermeating solutes than ICF • Isotonic solution—causes no change in cell volume • Concentrations of nonpermeating solutes in bath and ICF are the same • Normal saline (0.9% NaCl) is an example 12 Carrier-Mediated Transport • Transport proteins in membrane carry solutes into or out of cell (or organelle) • Specificity • Transport proteins are specific for particular solutes • Solute (ligand) binds to receptor site on carrier protein • Solute is released unchanged on other side of membrane • Three kinds of carriers 1. Uniport—carries one type of solute
• Example: Calcium pump 2. Symport—carries two or more solutes simultaneously in same direction (cotransport) • Example: sodium-glucose transporters 3. Antiport—Carries two or more solutes in opposite directions (countertransport) • Example: sodium-potasium pump removes Na+, brings in K+ • Three mechanisms of carrier-mediated transport • Facilitated diffusion, primary active transport, secondary active transport Facilitated diffusion • Carrier moves solute down its concentration gradient • Does not consume ATP • Solute attaches to binding site on carrier, carrier changes conformation, then releases solute on other side of membrane 13 Primary active transport • Carrier moves solute through a membrane up its concentration gradient • The carrier protein uses ATP for energy
• Examples: • Calcium pump (uniport) uses ATP while expelling calcium from cell to where it is already more concentrated • Sodium–potassium pump (antiport) uses ATP while expelling sodium and importing potassium into cell • Each pump cycle consumes one ATP and exchanges three Na+ for two K+ • Keeps K+ concentration higher and Na+ concentration lower within the cell than in ECF • Necessary because Na+ and K+ constantly leak through membrane • Half of daily calories utilized for Na+−K+ pump • Why? • Regulates solute concentration and thus osmosis and thus cell volume • Maintains negatively charged resting membrane potential • Maintains steep Na+ concentration gradient allowing for secondary active transport Secondary active transport
• Carrier moves solute through membrane but only uses ATP indirectly • Example: sodium-glucose transporter (SGLT) (symport) • Moves glucose into cell while simultaneously carrying sodium down its gradient • Depends on the primary transport performed by Na+- K+pump • Does not itself use ATP • Prevents loss of glucose to urine 14 Vesicular Transport • Moves large particles, fluid droplets, or numerous molecules at once through the membrane in vesicles—bubble-like enclosures of membrane • Endocytosis—vesicular processes that bring material into cell • Pinocytosis—“cell drinking,” taking in droplets of ECF containing molecules useful in the cell
• Membrane caves in, then pinches off pinocytic vesicle • Phagocytosis - engulfing large particles using pseudopods creating phagosome • Receptor-mediated endocytosis— particles bind to specific receptors on plasma membrane • Clathrin-coated vesicle • Exocytosis—discharging material from the cell Exocytosis and Transcytosis • Exocytosis—discharging material from the cell • Transcytosis • Transport of material across the cell by capturing it on one side and releasing it on the other • Receptor-mediated endocytosis moves it into the cell and exocytosis moves it out the other side 15 The Cell Interior
The Cytoskeleton • Network of protein filaments and cylinders • Composed of: microfilaments, intermediate fibers, microtubules • Microfilaments • 6 nm thick • Made of actin protein • Forms terminal web under p.m. • Intermediate filaments • 8–10 nm thick • Within skin cells, made of protein keratin • Give cell shape, resist stress • Microtubules • 25 nm thick • Consist of protofilaments made of protein tubulin • Radiate from centrosome; can come and go • Maintain cell shape, hold organelles, act as railroad tracks for walking motor proteins, make axonemes of cilia and flagella, form mitotic spindle 16
Organelles • Internal structures of a cell, carry out specialized metabolic tasks • Membranous organelles • Nucleus, mitochondria, lysosomes, peroxisomes, endoplasmic reticulum, and Golgi complex • Nonmembranous organelles • Ribosomes, centrosomes, centrioles, basal bodies The Nucleus • Largest organelle (5 μm in diameter) • Most cells have one nucleus • A few cell types are anuclear or multinucleate • Nuclear envelope—double membrane around nucleus • Perforated by nuclear pores formed by rings of proteins • Regulate molecular traffic through envelope • Hold the two membrane layers together • Nuclear envelope is supported by nuclear lamina
• Web of protein filaments • Provides points of attachment for chromatin • Helps regulate cell life cycle • Nucleoplasm—material in nucleus • Chromatin (thread-like) composed of DNA and protein • Nucleoli—masses where ribosomes are produced 17 Endoplasmic Reticulum • System of channels (cisternae) enclosed by membrane • Rough endoplasmic reticulum— parallel, flattened sacs covered with ribosomes • Continuous with outer membrane of nuclear envelope • Produces phospholipids and proteins of the plasma membrane • Synthesizes proteins that are packaged in other organelles or secreted from cell
• Smooth endoplasmic reticulum • Lack ribosomes • Cisternae more tubular and branching • Synthesizes steroids and other lipids • Detoxifies alcohol and other drugs • Calcium storage • Rough and smooth ER are functionally different parts of the same network Ribosomes • Ribosomes—small granules of protein and RNA • Found in nucleoli, in cytosol, and on outer surfaces of rough ER, and nuclear envelope • They “read” coded genetic messages (messenger RNA) and assemble amino acids into proteins specified by the code 18 Golgi Complex • System of cisternae that
synthesizes carbohydrates and puts finishing touches on protein synthesis • Receives newly synthesized proteins from rough ER • Sorts proteins, splices some, adds carbohydrate moieties to some, and packages them into membrane-bound Golgi vesicles • Some vesicles become lysosomes • Some vesicles migrate to plasma membrane and fuse to it • Some become secretory vesicles that store a protein product for later release Lysosomes and Peroxisomes • Lysosomes - Package of enzymes bound by a membrane • Functions • Intracellular hydrolytic digestion of proteins, nucleic acids, complex carbohydrates, phospholipids, and other substances • Autophagy—digestion of cell’s surplus organelles • Autolysis—“cell suicide”: digestion of a surplus cell by itself • Peroxisomes - Resemble lysosomes but contain different enzymes and are produced by endoplasmic reticulum
• Function is to use molecular oxygen to oxidize organic molecules • Neutralize free radicals, detoxify alcohol, other drugs, and a variety of blood- borne toxins • Break down fatty acids into acetyl groups for mitochondrial use in ATP synthesis • Reactions produce hydrogen peroxide H2O2 • Catalase breaks down excess peroxide to H2O and O2 • In all cells, but abundant in liver and kidney 19 Proteasomes • Proteasomes—hollow, cylindrical organelle that disposes of surplus proteins • Contain enzymes that break down tagged, targeted proteins into short peptides and amino acids Mitochondria • Specialized for synthesizing ATP • Surrounded by a double membrane • Inner membrane has folds
called cristae • Spaces between cristae called matrix • Matrix contains ribosomes, enzymes used for ATP synthesis, small circular DNA molecule • Mitochondrial DNA (mtDNA) • “Powerhouses” of the cell • Energy is extracted from organic molecules and transferred to ATP 20 Centrioles • Short cylindrical assembly of microtubules arranged in nine groups of three microtubules each • Two centrioles lie perpendicular to each other within the centrosome—small clear area in cell • Play important role in cell division
• Form basal bodies of cilia and flagella • Each basal body is a centriole that originated in centriolar organizing center and then migrated to the membrane Inclusions • Stored cellular products • Glycogen granules, pigments, and fat droplets 1 A General Orientation to Human Anatomy Expected Learning Outcomes • Describe a person in anatomical position. • Describe how to use the terms right and left in anatomical reference. • Identify the various planes in which a body might be dissected. • Describe the appearance of a body presented along various planes. • Describe the location of the body cavities and identify the major organs found in
each cavity. • List and describe the location of the major anatomical regions of the body. • Describe the location of the four abdominopelvic quadrants and the nine abdominopelvic regions and list the major organs located in each. • List and define the major directional terms used in anatomy. • Describe the location of body structures, using appropriate directional terminology. • Describe the location of structures of the body, using basic regional and systemic terminology. • List the organ systems of the human body and their major components. • Describe the major functions of each organ system. 2 Anatomical Position • Upright, feet flat on floor, palms forward • Left vs. Right
Directional Terms 3 Anatomical Planes • Sagittal – divides the body into right and left parts • Midsagittal or median – sagittal plane that lies on the midline • All others parasagittal • Frontal or coronal – divides the body into anterior and posterior parts • Transverse or horizontal – divides the body into superior and inferior parts Major Body Regions • Axial Region • Head • Neck (cervical region) • Trunk • Thoracic Region • Abdominal Region
• Appendicular Region • Upper limb • Lower Limbs 4 Further Division of the Abdominal Region • Two methods • Four Quadrants • Nine regions Body Cavities 5 Membranes of Body Cavities • Cranial cavity and vertebral canal lined by three layer meninges • Thoracic cavity has double layer serous membranes with lubrication serous fluid • Parietal and visceral pericardium create pericardial cavity with pericardial fluid • Two parietal and visceral pleura create pleural cavity with pleural fluid
Membranes of Body Cavities • Abdominopelvic cavity has double layer serous membranes • Parietal and visceral peritoneum create peritoneal cavity with peritoneal fluid • Some organs are intraperitoneal • Surrounded by peritoneum and connected to posterior by mesenteries • Some organs are retroperitoneal 6 The Human Organ Systems 1 1 Major Themes of Anatomy and physiology Expected Learning Outcomes • Define the terms anatomy and physiology. • Give specific examples to show the interrelationship between anatomy and physiology. • Describe, in order from simplest to most complex, the major levels of organization in the human organism.
• Give an example of each level of organization. • Define homeostasis • List the components of a feedback loop and explain the function of each. • Compare and contrast positive and negative feedback in terms of the relationship between stimulus and response. • Explain why negative feedback is the most commonly used mechanism to maintain homeostasis in the body. • Provide an example of a negative feedback loop that utilizes the nervous system to relay information. Describe the specific organs, structures, cells or molecules (receptors, neurons, CNS structures, effectors, neurotransmitters) included in the feedback loop. • Provide an example of a negative feedback loop that utilizes the endocrine system to relay information. Describe the specific cells or molecules (production cells, hormones, target cells) included in the feedback loop. • Provide an example of a positive feedback loop in the body. Describe the specific structures (organs, cells or molecules) included in the feedback loop. • Provide specific examples to demonstrate how organ systems respond to maintain homeostasis • Explain how different organ systems relate to one another to maintain homeostasis • Predict factors or situations affecting various organ systems
that could disrupt homeostasis. • Predict the types of problems that would occur in the body if various organ systems could not maintain homeostasis and allowed regulated variables (body conditions) to move away from normal. 2 Anatomy—The Study of Form • Examining structure of the human body • Inspection • Palpation – feeling with fingertips • Auscultation – listening to normal body sounds • Percussion – tapping and then listening to resulting sounds • Cadaver dissection • Cutting and separating human body tissues to reveal tissue relationships • Comparative anatomy • Study of multiple species to learn about form and evolution • Exploratory surgery • Medical imaging • Viewing the inside of the body without surgery • Radiology—branch of medicine concerned with imaging • Gross anatomy • Study of structures that can be seen with the naked eye • Histology
• Examination of tissues with microscope • Histopathology • Microscopic examination of tissues for signs of disease • Cytology • Study of structure and function of cells Anatomical Variation • Anatomy books show most common organization of structures • Some individuals lack certain muscles • Some individuals have an atypical number of vertebrae • Some individuals have an atypical number of certain organs (for example, kidneys) • Some individuals (1 in 8000) show situs inversus - left-right reversal of organ • https://www.anatomyatlases.org/AnatomicVariants/AnatomyHP. shtmlnt 3 Physiology—The Study of Function • Subdisciplines • Neurophysiology (physiology of nervous system)
• Endocrinology (physiology of hormones) • Pathophysiology (mechanisms of disease) • Comparative physiology • Study of different species to learn about body functions • Basis for much of our understanding of human physiology and the development of new drugs and medical procedures The Hierarchy of Complexity • Reductionism—large, complex systems can be understood by studying their simpler components • Essential to scientific thinking • Holism—“emergent properties” of the whole organism cannot be predicted from the properties of the separate parts • Humans are more than the sum of their parts 4 The Hierarchy of Complexity • Organism composed of organ systems • Organ systems composed of organs • Organs composed of tissues
• Tissues composed of cells • Cells composed of organelles • Organelles composed of molecules • Molecules composed of atoms Homeostasis and Negative Feedback • Homeostasis—the ability to detect change, activate mechanisms that oppose it, and thereby maintain relatively stable internal conditions • Claude Bernard (1813–78) • Noted fairly constant internal conditions despite changing external conditions (for example, temperature) • Walter Cannon (1871–1945) • Coined the term homeostasis • Negative feedback allows for dynamic equilibrium within a limited range around a set point • The body senses a change and “negates” or reverses it • Loss of homeostatic control causes illness or death 5
Negative Feedback in Thermoregulation Homeostasis and Negative Feedback • Because feedback mechanisms alter the original changes that triggered them, they are called feedback loops. • Homeostasis in body temperature • If too warm, vessels dilate in the skin and sweating begins (heat-losing mechanism) • If too cold, vessels in the skin constrict and shivering begins (heat-gaining mechanism) 6 Homeostatic Compensation for a Postural Change in Blood Pressure • Receptor—structure that senses change in the body (e.g., stretch receptors above heart that monitor blood pressure) • Integrating (control) center— control center that processes the sensory information, “makes a decision,” and directs the response (e.g., cardiac center of the brain)
• Effector— cell or organ that carries out the final corrective action to restore homeostasis (e.g., the heart) Homeostatic Compensation for Blood Calcium Levels • Ca2+ levels need to be maintained at 9.2 – 10.4 mg/dL for proper nervous and muscle funtion • Parathyroid hormone (PTH) secreted by parathyroid glands on posterior surface of thyroid when calcium levels low in blood • PTH raises calcium blood level by four mechanisms 1. Stimulates osteoclast and bone resorption 2. Inhibits osteoblasts and bone deposition 3. Promotes calcium reabsorption by kidneys, so less lost in urine 4. Promotes phosphate excretions by kidneys, so less bone deposition Figure 7.16b
7 Positive Feedback and Rapid Change • Self-amplifying cycle • Leads to greater change in the same direction • Feedback loop is repeated—change produces more change • Normal way of producing rapid changes • Examples include: childbirth, blood clotting, protein digestion, and generation of nerve signals • Can sometimes be dangerous • Example Heat Shock • Body temperature above 40C (104˚F) increases speed of chemical reactions, increasing heat • Which increase the speed of reactions • Which increase heat • Until death at 45C (113˚F) Positive Feedback in Childbirth

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104 Genetics and cellular functionLearning Objective.docx

  • 1. 1 04 Genetics and cellular function Learning Objectives • With respect to nucleic acids: • Identify the monomers and polymers. • Compare and contrast general molecular structure. • Define the terms genetic code, transcription and translation. • Explain how and why RNA is synthesized. • Explain the roles of tRNA, mRNA, and rRNA in protein synthesis. • Define the term cellular respiration. • With respect to glycolysis, the Krebs (citric acid or TCA) cycle, and the electron transport chain: compare and contrast energy input, efficiency of energy production, oxygen use, by-products and cellular location. • Referring to a generalized cell cycle, including interphase and the stages of mitosis: • Describe the events that take place in each stage. • Identify cells that are in each stage. • Analyze the functional significance of each stage. • Distinguish between mitosis and cytokinesis.
  • 2. • Describe DNA replication. • Analyze the interrelationships among chromatin, chromosomes and chromatids. • Give examples of cell types in the body that divide by mitosis and examples of circumstances in the body that require mitotic cell division. • Compare and contrast the processes of mitosis and meiosis. • Provide specific examples to demonstrate how individual cells respond to their environment (e.g., in terms of organelle function, transport processes, protein synthesis, or regulation of cell cycle) in order to maintain homeostasis in the body. • Predict factors or situations that could disrupt organelle function, transport processes, protein synthesis, or the cell cycle. • Predict the types of problems that would occur if the cells could not maintain homeostasis due to abnormalities in organelle function, transport processes, protein synthesis, or the cell cycle. 2 DNA and RNA—The Nucleic Acids DNA Structure • Deoxyribonucleic acid (DNA)—
  • 3. long, thread-like molecule with 2 nm diameter, but varied length • 46 DNA molecules in nucleus of most human cells • Average length about 43,000 μm each • DNA (and other nucleic acids) are polymers of nucleotides • Nucleotide consists of a sugar, phosphate group, and nitrogenous base • A single DNA nucleotide • One deoxyribose sugar • One phosphate group • One nitrogenous base 3 Nitrogenous Bases • Purines—double ring • Adenine (A) • Guanine (G) • Pyrimidines—single ring • Cytosine (C)
  • 4. • Thymine (T) • Uracil (U) (not found in DNA, only found in RNA) DNA Structure • Phosphate and Sugar unite by covalent bonds to form “backbone” • Nitrogenous bases of two backbones united by hydrogen bonds • A purine on one strand always bound to a pyrimidine on the other • A–T two hydrogen bonds • C–G three hydrogen bonds • Double helix shape of DNA (resembles spiral staircase) • Law of complementary base pairing • One strand determines base sequence of other 4 Chromatin and Chromosomes • Most human cells have 2 million μm (2m) of DNA • Nucleosome - DNA winds around eight
  • 5. histone proteins (like thread around spool) • Chromatin consists - thousands of repeating nucleosomes • Occurs as 46 chromosomes in most cells • In nondividing cells, chromatin is so slender it cannot be seen with light microscope • Granular appearance under electron microscope • Chromatin thrown into complex, irregular loops and coils • 1,000 times shorter than original molecule Chromosomes • When preparing to divide, cell makes copy of all nuclear DNA • Each chromosome then consists of two parallel filaments of identical DNA - sister chromatids • Becomes visible with light microscope • Chromatids are joined at constricted centromere • Kinetochores—proteins on each side of centromere 5
  • 6. RNA Structure and Function • Ribonucleic acids (RNAs) – a polymer of nucleotides that resemble DNA but • Ribose sugar instead of deoxyribose • Uracil instead of Thymine • RNA is usally single stranded and much shorter in length than DNA • Three important RNAs for protein synthesis • Messenger RNA (mRNA) • Ribosomal RNA (rRNA) • Transfer RNA (tRNA) Genes and Their Action 6 What Is a Gene? • 46 human chromosomes come in two sets of 23 chromosomes (one from each parent) • Genome—all the DNA in one 23-chromosome set • Genomics—study of the whole genome and how it affects structure and function of the whole organism • Genome is 3.1 billion nucleotides
  • 7. • Humans have about 20,000 genes • Only about 2% of total DNA is genes • Other 98% is noncoding DNA that plays role in chromosome structure and gene regulation • Gene—an information-containing segment of DNA that codes for the production of a molecule of RNA that plays a role in synthesizing one or more proteins • Amino acid sequence of a protein is determined by the nucleotide sequence in the DNA The Genetic Code • Body can make millions of different proteins (the proteome), from just 20 amino acids, and encoded by genes made of just four nucleotides (A, T, C, G) • Genetic code—a system that enables these four nucleotides to code for amino acid sequences of all proteins • Minimum code to symbolize 20 amino acids is three nucleotides per amino acid • Base triplet - a sequence of three DNA nucleotides that stands for one amino acid • Codon - the 3-base sequence in mRNA
  • 8. • 64 possible codons available to represent the 20 amino acids • 61 code for amino acids; 3 are stop codons • Stop codons—UAG, UGA, and UAA: signal “end of message,” like a period at the end of a sentence • Start codon—AUG codes for methionine, and begins the amino acid sequence of the protein 7 Protein Synthesis • All body cells, except sex cells and some immune cells, contain identical genes • But different genes are activated in different cells • Any given cell uses one-third to two-thirds of its genes while the rest are “dormant” • When a gene is activated, mRNA complementary to the genes is synthesized in the nucleus • Transcription • mRNA Migrates from the nucleus to cytoplasm where it codes for amino acids used to make protein • Translation
  • 9. Transcription • Transcription - copying genetic instructions from DNA to mRNA • RNA polymerase - binds to certain DNA sequences that signal start (e.g., TATATA) and synthesize mRNA copy • RNA polymerase opens up the DNA helix and reads bases from one strand of DNA • RNA polymerase rewinds the DNA helix behind it so it can be transcribed again • Transcription stops to certain DNA sequences called the Terminator 8 Alternative Splicing • Transcription actually makes Pre-mRNA • Pre-mRNA has: • Intervening introns that are removed by nuclear enzymes • Exons that will form “mature” mRNA that is exported from nucleus • Alternative splicing - variations in the way exons are spliced allow for a variety of proteins to be produced from one gene • Finally cap (for ribosome binding) has to be added
  • 10. Translation • Translation - process that converts the language of nucleotides into the language of amino acids • Three main participants in translation • mRNA carries code from nucleus to cytoplasm • Transfer RNA (tRNA) delivers a single amino acid to the ribosome for it to be added to growing protein chain • Contains an anticodon - series of 3 nucleotides that are complementary to codon of mRNA • Attached to the correct amino acid • Ribosomes - organelles that read the message • Found free in cytosol, on rough ER, and on nuclear envelope • Consist of large and small subunits, where each subunit is made of several enzymes and ribosomal RNA (rRNA) molecules 9 Translation - Initiation • Three steps to translation: Initiation, Elongation, Termination 1. Initiation
  • 11. • Small ribosomal subunit binds to mRNA near cap and slide along until • Initiator tRNA (bearing methionine) pairs with start codon • Large ribosomal subunit joins the complex and the now fully formed ribosome begins reading bases Translation – Elongation 2. Elongation • Next tRNA (with its amino acid) binds to ribosome while its anticodon pairs with next codon of mRNA • Peptide bond forms between methionine and second amino acid • Ribosome slides to read next codon and releases initiator tRNA (empty) • Next tRNA with appropriate anticodon brings its amino acid to ribosome • Another peptide bond forms (between 2nd and 3rd amino acids) • Process continually repeats, extending peptide to a protein 10 Translation - Termination • Three steps to translation: Initiation, Elongation, Termination 3. Termination • When ribosome reaches stop codon a release factor binds to it
  • 12. • Finished protein breaks away from ribosome • Ribosome dissociates into two subunits Review of Transcription and Translation 11 Protein Processing and Secretion 1 • Protein synthesis is not finished when the amino acid sequence (primary structure) has been assembled • Chaperone proteins help fold protein into precise secondary and tertiary structures for proper function • Proteins to be used in the cytosol are made on free ribosomes in the cytosol • Proteins headed for lysosomes, secretion, or integral membrane proteins are made on ribosomes on the rough ER • mRNA/ribosome migrates docks on surface of ER and feeds polypeptide to interior • Some post-translational modification (e.g. disulfide bridges, glycosylation) occurs in ER lumen • When rough ER is finished with protein • Pinches off transport vesicle coated with clathrin • Vesicles detach from ER and carry protein to the nearest cisterna of Golgi complex
  • 13. Protein Processing and Secretion 2 • ER derived vesicles fuse with Golgi cisterna • Golgi complex further modifies the protein • Often adds carbohydrate chains and assembles glycoproteins • Golgi cisterna farthest from ER buds off new coated Golgi vesicles containing finished protein • Some Golgi vesicles become lysosomes • Other Golgi vesicles become secretory vesicles and migrate to plasma membrane, fuse to it, and release their cell product by exocytosis • Other Golgi vesicles migrate to plasma membrane, fuse to it, and deliver integral transmembrane proteins 12 Synthesizing Compounds Other Than Proteins • Cells synthesize glycogen, fat, steroids, phospholipids, pigments, and
  • 14. other compounds • No genes for these products, but their synthesis is under indirect genetic control • They are produced by enzymatic reactions, and enzymes are proteins encoded by genes • Example: production of testosterone (a steroid) • A cell of the testes takes in cholesterol • Enzymatically converts it to testosterone • Only occurs when genes for enzyme are active DNA Replication and the Cell Cycle 13 DNA Replication • Before a cell divides, it must duplicate its DNA so it can give a complete copy of all its genes to each daughter cell • Since DNA controls all cellular function, this replication process must be very exact • Law of complementary base pairing - we can predict the base sequence of one DNA strand if we know the sequence of the other
  • 15. • Four steps of DNA replication: unwinding, unzipping, building new DNA strands, repackaging 1. DNA unwinds from histones 2. DNA helicase unzips segment of double helix exposing bases • Replication fork - the point of DNA opening DNA Replication 2 • Four steps of DNA replication: unwinding, unzipping, building new DNA strands, repackaging 1. DNA polymerase builds new DNA strands • Polymerase reads exposed bases and matches complementary free nucleotides • Separate polymerase molecules work on each strand proceeding in opposite directions • DNA polymerase does make mistakes, but • Double checks the new base pair and tends to replace incorrect, biochemically unstable pairs with more stable, correct pairs • Result is only one error per 1 billion bases replicated - Mutation • Some mutations cause no ill effects, others kill the cell, turn it cancerous, or cause genetic defects in future generations 2. Newly made DNA is repackaged • With thousands of polymerase molecules working simultaneously on the DNA, all 46 chromosomes are replicated in 6 to 8
  • 16. hours • Millions of histones are made in the cytoplasm while DNA is replicated and they are transported into the nucleus soon after DNA replication ends • Each new DNA helix wraps around the histones to make new nucleosomes 14 The Cell Cycle • Cell cycle—cell’s life from one division to the next • Includes interphase and mitotic phase • Interphase includes three subphases • G1, S, G2 • Mitotic phase includes multiple subphases • Prophase, Metaphase, Anaphase, Telophase Mitosis 1 • Meiosis is cell division resulting in two daughter cells (gametes) with half the genetic information • Mitosis is cell division resulting in two genetically identical
  • 17. daughter cells • Functions of mitosis • Development of the individual from one fertilized egg to roughly 50 trillion cells • Growth of all tissues and organs after birth • Replacement of cells that die • Repair of damaged tissues • Four phases of mitosis • Prophase, metaphase, anaphase, telophase 15 Mitosis 2 • Prophase • Genetic material condenses into 46 compact chromosomes • Two chromatids per chromosome • Nuclear envelope disintegrates • Centrioles sprout spindle fibers (long microtubules) • Spindle fibers push centriole
  • 18. pairs apart • Some spindle fibers attach to kinetochores of centromeres of chromosomes • Metaphase • Chromosomes are aligned on metaphase plate • Spindle fibers complete mitotic spindle • Shorter microtubules from centrioles complete an aster which anchors itself to inside of cell membrane Mitosis 3 • Anaphase • Enzyme cleaves two sister chromatids apart at centromere • Single-stranded daughter chromosomes migrate to each pole of the cell as motor proteins in kinetochores crawl along spindle fibers • Telophase • Chromosomes cluster on each
  • 19. side of the cell • Rough ER makes new nuclear envelope around each cluster • Chromosomes uncoil to chromatin • Mitotic spindle disintegrates • Each nucleus forms nucleoli 16 Mitosis 4 • Cytokinesis—division of cytoplasm into two cells • Telophase is the end of nuclear division but overlaps cytokinesis • Achieved by myosin protein pulling on actin in the terminal web of cytoskeleton • Creates cleavage furrow around the equator of cell • Cell eventually pinches in two Chromosomes and Heredity
  • 20. 17 Chromosomes and Heredity • Heredity—transmission of genetic characteristics from parent to offspring • Karyotype—chart of 46 chromosomes laid out in order by size • 23 pairs—the two members of each pair are called homologous chromosomes • 1 chromosome from each pair inherited from each parent • 22 pairs called autosomes • Look alike and carry the same genes • 1 pair of sex chromosomes (X and Y) • Female has homologous pair of X chromosomes • Male has one X and one much smaller Y chromosome • Diploid (2n) —describes any cell with 23 pairs of chromosomes (somatic cells) • Haploid (n) —describes cells containing half as many chromosomes (23 unpaired) as somatic cells; that is, sperm and egg cells • Fertilization restores diploid (2n) number to the fertilized egg and the somatic cells arise from it
  • 21. Genes and Alleles • Location of a particular gene on a chromosome called locus • Different forms of gene at same locus on two homologous chromosomes called alleles • Genotype - alleles an individual possesses for a particular trait • Homozygous individuals—two identical alleles for the trait • Heterozygous individuals—different alleles for that gene • Phenotype - an observable trait • An allele is expressed if it shows in the phenotype of an individual • Dominant allele (represented by capital letter) • If present, corresponding trait is usually seen in the individual • Masks effect of recessive allele • Often produces protein responsible for visible trait • Recessive allele (represented by lowercase letter) • Corresponding trait only seen when recessive allele present on both homologous chromosomes • Often codes for a nonfunctional variant of the protein • Punnett square - diagram showing possible genotype and phenotype outcomes from parents of known genotype 18 Punnett Square
  • 22. • Cleft (C) is dominant to uncleft chin (c) • CC, Cc = cleft chin • cc = uncleft chin • Can two parents with cleft chin produce child with uncleft chin? Sex Linkage • Sex-linked traits—carried on X or Y chromosome, and therefore tend to be inherited by one sex more than the other • Much more common for trait to be on X, as Y as very few genes • Recessive color blindness allele on X, no gene locus for trait on Y, so color blindness more common in men (mother is carrier in illustrated example) 19 Multiple Alleles, Codominance, and Incomplete Dominance • Gene pool - genetic makeup of whole population (an individual can only have two alleles, but population can have many) • Multiple alleles—more than two allelic forms of gene
  • 23. • Example: three alleles for ABO blood types • IA, IB, i alleles for ABO blood types • Codominance—both alleles equally dominant • Both are phenotypically expressed • Example: IAIB = type AB blood • Incomplete dominance • Heterozygous individual shows phenotype intermediate between traits each allele would have produced alone • Example: familial hypercholesterolemia EDU 508 – Educational Research Methods COURSE DESCRIPTION In many ways, progress and change within education and training organizations and systems is driven by research. This course enables students to choose a topic to research and guides them through the decision process of methodological approaches, research procedures and evaluation and interpretation of research results. Additionally, students learn ethical procedures and formal academic writing that can be applied to careers in education and training. INSTRUCTIONAL MATERIALS Required Resources Mertler, Craig, (2019) A. Introduction to Educational Research (2nd ed.) Thousand Oaks, CA: SAGE COURSE LEARNING OUTCOMES 1. Determine the best research methodology for a given educational research topic. 2. Conduct a literature review for a given research topic.
  • 24. 3. Describe ethical considerations in the research process. 4. Write an educational research proposal. 5. Interpret educational research results. COURSE TOOLS AND TUTORIALS The following tools and tutorials are resources for this course and will help you succeed at exploring research articles. They should be completed within the first week. · Complete the tutorial in the Course Tools tab in your course shell and the required quiz in Week 1 entitled “Genius Navigator” to earn your Genius Navigator Badge. WEEKLY COURSE SCHEDULE The standard requirement for a 4.5 credit hour course is for students to spend 13.5 hours in weekly work. This includes preparation, activities, and evaluation regardless of delivery mode. Week Preparation, Activities, and Evaluation 1 Preparation · Read Chapter 1: What is Educational Research · Read Chapter 2: Overview of the Educational Research Process · Read the Education Research Overview located here: http://libdatab.strayer.edu/login?url=https://search.ebscohost.co m/login.aspx?direct=true&db=e0h&AN=27170113&site=eds- live&scope=site · Watch – Video from American Educational Research Association on the importance and purpose of educational research - https://www.youtube.com/watch?v=uWOP6H5uocc · Watch – The Pursuit of Ignorance on how research is not the pursuit of knowledge, but of what we don’t know - https://www.ted.com/talks/stuart_firestein_the_pursuit_of_ignor ance#t-581382 · Complete the Course Tools and Tutorials in the online course
  • 25. Activities · Course Expectations and Introductions · Throughout this course, you will complete activities that simulate research and produce a research paper. To streamline the research process, the suggested sample population for your research is your classmates. Therefore, your research topic should be related to college students. · This week, begin to think about a research topic you would like to study for this class. You must have your topic selected by the end of next week. · Discussions (15 points) Evaluation · Genius Navigator Quiz (10 points) 2 Preparation · Read Chapter 3: Identifying a Research Problem · Read Chapter 4: Ethics in Educational Research · Watch Crash Course Sociology – Sociological Research Methods: https://www.youtube.com/watch?v=QwhK-iEyXYA · This video explains how researchers form a question and a hypothesis, collect data, and analyze that data · Watch Crash Course Statistics: Henrietta Lacks, the Tuskegee Experiment, & Ethical Data Collection: https://youtu.be/CzNANZnoiRs · Read Chapter 1: The Selection of a Research Approach Activities · Discussion (15 points) Evaluation · None 3 Preparation · Read Chapter 5 Reviewing Related Research · Read Ten Simple Steps for Writing a Literature
  • 26. Review by Marco Pautasso,located on the course shell. · Read the APA Flow Chart located on the course shell · Watch Crash Course Statistics: Science Journalism: https://youtu.be/ZwqOoD17_LU Activities · Discussion (15 points) Evaluation · Assignment 1: The Scavenger Hunt (100 points) 4 Preparation · Read Chapter 6: Qualitative Research Methods · Watch Crash Course Statistics Correlation Doesn’t Equal Causation: https://youtu.be/GtV-VYdNt_g Activities · Discussion (15 points) Evaluation · None 5 Preparation · Read Chapter 7: Quantitative Research Methods · Watch Crash Course Statistics: The Normal Distribution: https://youtu.be/rBjft49MAO8 Activities · Discussion (15 points) Evaluation · Assignment 2: The Literature Review (200 points) 6 Preparation · Read Chapter 10: Writing a Research Proposal · Watch Crash Course Statistics: Sampling Methods and Bias with Surveys: https://youtu.be/Rf-fIpB4D50 Activities · Discussion (15 points) Evaluation · None
  • 27. 7 Preparation · Read Chapter 12: Quantitative Data Collection · Read Research Starters: Inferential Statistics located in the course shell. · Watch Crash Course Statistics: Test Statistics: https://youtu.be/QZ7kgmhdIwA · Watch Crash Course Statistics: T- Tests: https://youtu.be/AGh66ZPpOSQ · Reference: T-Test with a link to an excel spreadsheet where you can calculate a T- Test: https://researchbasics.education.uconn.edu/t-test/# Activities · Discussion (15 points) Evaluation · Assignment 3: Research Paper– The Foundation (200 points) 8 Preparation · Read Chapter 13: Quantitative Data Analysis Activities · Discussion (15 points) · Post your survey tool to the Survey Tool Discussion Board (50 points) Evaluation · None 9 Preparation · Read Chapter 14: Writing a Final Research Report · Look at the Is It Plagiarism? infographic in the course shell · Watch The Punishable Perils of Plagiarism - https://www.youtube.com/watch?v=SrjoaaIxaJI Activities · Discussion (15 points) · Collect your final data and close your survey tool.
  • 28. Evaluation · None 10 Preparation · Read Chapter 8: Mixed-Methods Research · Read Chapter 9: Action Research Activities · Discussion (15 points) Evaluation · Assignment 4: Research Paper – Putting it All Together (290 points) 11 Preparation · Reading(s): None Activities · Discussion Evaluation · None GRADING SCALE – GRADUATE Assignment Total Points % of Grade Genius Navigator Quiz 10 1% Assignment 1: The Scavenger Hunt 100 10% Assignment 2: Research Paper – The Literature Review 200 20% Assignment 3: Research Paper – The Foundation 200 20%
  • 29. Assignment 4: Research Paper – Putting it All Together 290 29% Post Survey Tool on Survey Discussion Board 50 5% Participation (10 discussions worth 15 points each) 150 15% Totals 1,000 100% Points Percentage Grade 900 – 1,000 90% – 100% A 800 – 899 80% – 89% B 700 – 799 70% – 79% C Below 700 Below 70% F Supplemental Resources Educational Research Websites American Educational Research Journal. (2013). General format. Retrieved from http://aer.sagepub.com/
  • 30. American Educational Research Association. (2013). General format. Retrieved from http://www.aera.net/ American Institutes for Research (2103). General format. Retrieved from http://www.air.org/ The Chronicle of Higher Education. (2013). General format. Retrieved from http://chronicle.com/section/Home/5 EDU 508 – Educational Research Methods © 2019 Strayer University. All Rights Reserved. This document contains Strayer University confidential and proprietary information and may not be copied, further distributed, or otherwise disclosed in whole or in part, without the expressed written permission of Strayer University. EDU 508 STUDENT GUIDE 1192 (12-03-2018) Page 2 of 16 Research Assignment Overview For the purpose of this class, you will choose a research topic and design a 3-5 question survey to study that topic. This project is designed to give you an idea of how to conduct educational research, how to interpret those results, and how those results can be used to affect teaching methods, curriculum, school policy, and educational law. The core of your research project will be your research instrument, e.g. your survey. Surveys must collect data anonymously (i.e. they don’t ask for names or other information that can be used to identify someone) and be easily accessible such as through a web link.
  • 31. The following survey tools are listed in your book. You may also choose to use your own tool such as GoogleDocs to create a survey and collect data. Explore the tools below and see which one you like the best. All will require you to create an account but have free access for trial accounts and individual/limited use. · KwikSurveys (www.kwiksurveys.com) · Murvey (www.murvey.com) · Qualtrics (www.qualtrics.com) · QuestionPro (www.questionpro.com) · SurveyMonkey (www.surveymonkey.com) · Zoho Survey (www.zoho.com/survey) · Zoomerang (www.zoomerang.com) You will need to have your survey tool selected and your survey questions written no later than week 7 so you can post it in week 8. Research Study Planning Guidelines This course is designed as a series of activities and assignments that build upon each other cumulatively and result in a complete research paper. Therefore, it is important that you complete the activities and assignments in the weeks required to be able to progress forward. You are encouraged to work ahead, but at a minimum the activities should be completed in the weeks suggested below. The following checklist is provided to help you prepare for and complete the assignments in this course. Specific assignment instructions are located in the online course. The checklist does not include readings, and discussion questions. Activity
  • 32. Complete Activity in Week To Support Assignment # Genius Navigator tutorial and quiz located in the online course. 1 1 through 4 Sign up for a survey account. 1-7 1 through 4 Review research related to your research topic. 1 through 7 3 Develop questions for your survey. 5-7 4 Distribute questions to your classmates via the survey discussion board. 8 4 Download data from your survey tool. 9 4 Analyze data from your survey tool and report on descriptive statistics. 10 4 Assignment 1: The Scavenger Hunt Due Week 3 and worth 100 points Let’s put your investigative skills to work! In this assignment, visit the Strayer online library located in research.strayer.com or the Resource Center tab in Blackboard and find four (4) peer- reviewed quantitative articles related to your topic. Read each article.
  • 33. Write a three to five (3-5) page paper in which you: 1. Summarize each article [approximately one to two (1-2) paragraphs per article] and identify the: a. Purpose of the research. b. Problem statement. c. Gaps in literature that studied the problem. d. Research question and/or hypotheses. e. Theory or conceptual framework. f. Findings of the research. 2. Describe one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. 3. Provide a preliminary reference page in APA format of the articles you summarized. 4. Include at least four (4) peer-reviewed quantitative or qualitative articles related to your topic. Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Conduct a literature review for a given research topic. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 100
  • 34. Assignment 1: The Scavenger Hunt Criteria Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Summarize each article related to research topic. Weight: 50% Did not submit or incompletely summarized each article and/or articles were not related to research topic. Partially summarized each article and/or articles were partially related to the research topic. Satisfactorily summarized each article and articles were related to the research topic. Thoroughly summarized each article and each article was related to the research topic. 2. Describe one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Weight: 30% Did not submit or incompletely described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Partially described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Satisfactorily described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. Thoroughly described one to two (1-2) aspects of each article that are relevant to the research topic you have chosen. 3. Writing Mechanics, Grammar, and Formatting Weight: 10% Serious and persistent errors in grammar, spelling, punctuation, or formatting.
  • 35. Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting. 4. Appropriate use of APA in-text citations and reference section Weight: 10% Lack of in-text citations and / or lack of reference section. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. Assignment 2: Research Paper – The Literature Review Due Week 5 and worth 200 points For this assignment, you will create the second part of your research paper. The literature review should consist of a total of seven to ten (7-10) articles related to your research topic. These articles may include any articles you have previously found throughout this course. You should use the headings below for the sections of your paper. Write a three to five (3-5) page paper in which you: 1. Identify two to three (2-3) common themes in the literature. 2. Contrast the findings and results of the literature. 3. Identify gaps in the literature. 4. Summarize the literature as it relates to your topic. 5. Include seven to ten (7-10) peer-reviewed quantitative or qualitative articles related to your topic.
  • 36. Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Conduct a literature review for a given research topic. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 200 Assignment 3: Research Paper Part 2 – The Literature Review Criteria Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Identify two to three (2-3) common themes in the literature. Weight: 20% Did not submit or incompletely identified two to three (2-3) common themes in the literature. Partially identified two to three (2-3) common themes in the literature.
  • 37. Satisfactorily identified two to three (2-3) common themes in the literature. Thoroughly identified two to three (2-3) common themes in the literature. 2. Contrast the findings and results of the literature. Weight: 20% Did not submit or incompletely contrasted the findings and results of the literature. Partially contrasted the findings and results of the literature. Satisfactorily contrasted the findings and results of the literature. Thoroughly contrasted the findings and results of the literature. 3. Identify gaps in the literature. Weight: 20% Did not submit or incompletely identified gaps in the literature. Partially identified gaps in the literature. Satisfactorily identified gaps in the literature. Thoroughly identified gaps in the literature. 4. Summarize the literature as it relates to your topic. Weight: 10% Did not submit or incompletely summarized the literature as it relates to your topic. Partially summarized the literature as it relates to your topic. Satisfactorily summarized the literature as it relates to your topic. Thoroughly summarized the literature as it relates to your topic. 5. Writing Mechanics, Grammar, and Formatting Weight: 10% Serious and persistent errors in grammar, spelling, punctuation, or formatting. Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting.
  • 38. 6. 7-10 articles with appropriate use of APA in-text citations and reference section Weight: 10% Lack of in-text citations, lack of reference section and/or insufficient number of articles. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. Assignment 3: Research Paper – The Foundation Due Week 7 and worth 200 points If you have ever asked a question, wondered why something is as it is, or tried to understand an event, you have engaged in research. For this assignment, you will create the first part of your research paper. You should use the headings below for the sections of your paper. You will craft the framework of your research using the articles you collected and summarized from Assignment 1 and / or other articles you found that relate to your research topic. Assignments 2, 3, and 4 will all build on each other to create one comprehensive research paper. Each time you submit an assignment, your instructor will provide feedback that you can use moving forward with the other parts of the research paper. Write a four to five (7-10) page paper in which you: 1. Introduction Section - Describe the: a. Introduction to your topic. b. Purpose of your research.
  • 39. c. Problem statement. 2. Literature Review - Summarize the literature you collected related to your topic. (This will mainly be from Assignment 2.) 3. Research Question - Identify the: a. Gap(s) in the literature. b. Research question or hypotheses of your topic. c. Proposed theory for your research. 4. Include at least six (6) peer-reviewed articles related to your topic. Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Determine the best research methodology for a given educational research topic. · Conduct a literature review for a given research topic. · Describe ethical considerations in the research process. · Write an educational research proposal. · Interpret educational research results. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 200 Assignment 2: Research Paper Part 1 – The Foundation Criteria
  • 40. Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Wrote a complete introduction. Weight: 40% Did not submit or incompletely wrote an introduction. Partially wrote an introduction. Satisfactorily wrote an introduction. Thoroughly wrote an introduction. 2. Summarize the literature you collected related to your topic. Weight: 15% Did not submit or incompletely summarized the literature you collected related to your topic. Partially summarized the literature you collected related to your topic. Satisfactorily summarized the literature you collected related to your topic. Thoroughly summarized the literature you collected related to your topic. 3. Research question section is organized and addresses the gaps in the literature. Weight: 25% Did not submit or incompletely wrote the research question section that is organized and addresses the gaps in the literature. Partially identified wrote the research question section that is organized and addresses the gaps in the literature. Satisfactorily wrote the research question section that is organized and addresses the gaps in the literature. Thoroughly wrote the research question section that is organized and addresses the gaps in the literature.
  • 41. 4. Writing Mechanics, Grammar, and Formatting Weight: 10% Serious and persistent errors in grammar, spelling, punctuation, or formatting. Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting. 5. Appropriate use of APA in-text citations, number of quality sources, and reference section Weight: 10% Lack of in-text citations, number of quality sources, and / or lack of reference section. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. Assignment 4: Research Paper: Putting it All Together Due Week 10 and worth 290 points What do reporters, crime scene investigators, and sports broadcasters have in common? All of these occupations are focused on reporting the results from data or information. The final part of your research paper is about the data procedures, reporting, and interpretation of the results of your research topic. For this assignment, you will create the last part of your research paper. Build on your paper from Assignments 2 and 3, and integrate feedback from your instructor. You should use the
  • 42. headings below for the sections of your paper. Write a twelve to fifteen (12-15) page paper (this includes the work you already completed in Assignments 2 and 3) in which you: These items you should have already completed in Assignments 2 and 3: 1. Describe the: a. Introduction to your topic. b. Purpose of your research. c. Problem statement. 2. Summarize the literature you collected related to your topic. 3. Identify the: a. Gap(s) in the literature. b. Research question or hypotheses of your topic. c. Proposed theory for your research. 4. Identify two to three (2-3) common themes in the literature. 5. Contrast the findings and results of the literature. 6. Include seven to ten (7-10) peer-reviewed quantitative or qualitative articles related to your topic. These items are new for Assignment 4: 1. Describe the participants in the study. 2. Methodology a. Describe the research instrument participants completed in the study. b. Explain the procedures that you conducted. 3. Perform the data analysis. 4. Interpret Results a. Summarize your findings. b. Interpret the results of the data analysis. c. Describe the limitations of your research. 5. Write a conclusion where you pose additional research questions that can be studied from your research.
  • 43. Remember to address the feedback from your instructor for Assignments 2 and 3. Your assignment must follow these formatting requirements: · Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. · Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: · Determine the best research methodology for a given educational research topic. · Conduct a literature review for a given research topic. · Describe ethical considerations in the research process. · Write an educational research proposal. · Interpret educational research results. Grading for this assignment will be based on answer quality, logic / organization of the paper, and language and writing skills, using the following rubric. Points: 290 Assignment 4: Research Paper – Putting it All Together Criteria Unacceptable Below 70% F Fair 70-79% C Proficient 80-89% B Exemplary 90-100% A 1. Included material from assignments 1-3.
  • 44. Weight: 2% Did not submit or incompletely included material from assignments 1-3. Partially included material from assignments 1-3. Satisfactorily included material from assignments 1-3. Thoroughly included material from assignments 1-3. 7. Describe the participants in the study. Weight: 10% Did not submit or incompletely described the participants in the study. Partially described the participants in the study. Satisfactorily described the participants in the study. Thoroughly described the participants in the study. 8. Describe the instrument participants completed in the study Weight: 10% Did not submit or incompletely described the instrument participants completed in the study. Partially described the instrument participants completed in the study. Satisfactorily described the instrument participants completed in the study. Thoroughly described the instrument participants completed in the study. 9. Explain the procedures that you conducted. Weight: 10% Did not submit or incompletely explained the procedures that you conducted. Partially explained the procedures that you conducted. Satisfactorily explained the procedures that you conducted. Thoroughly explained the procedures that you conducted. 10. Perform the data analysis. Weight: 10% Did not submit or incompletely performed the data analysis. Partially performed the data analysis. Satisfactorily performed the data analysis. Thoroughly performed the data analysis.
  • 45. 11. Summarize your findings. Weight: 5% Did not submit or incompletely summarized your findings. Partially summarized your findings. Satisfactorily summarized your findings. Thoroughly summarized your findings. 12. Interpret the results of the data analysis. Weight: 5% Did not submit or incompletely interpreted the results of the data analysis. Partially interpreted the results of the data analysis. Satisfactorily interpreted the results of the data analysis. Thoroughly interpreted the results of the data analysis. 13. Summarize the findings and limitations of your research. Weight: 5% Did not submit or incompletely summarized the findings and limitations of your research. Partially summarized the findings and limitations of your research. Satisfactorily summarized the findings and limitations of your research. Thoroughly summarized the findings and limitations of your research. 15. Writing Mechanics, Grammar, and Formatting Weight: 5% Serious and persistent errors in grammar, spelling, punctuation, or formatting. Partially free of errors in grammar, spelling, punctuation, or formatting. Mostly free of errors in grammar, spelling, punctuation, or formatting. Error free or almost error free grammar, spelling, punctuation, or formatting. 16. Appropriate use of APA in-text citations and reference section Weight: 5%
  • 46. Lack of in-text citations and / or lack of reference section. In-text citations and references are provided, but they are only partially formatted correctly in APA style. Most in-text citations and references are provided, and they are generally formatted correctly in APA style. In-text citations and references are error free or almost error free and consistently formatted correctly in APA style. 17. Information Literacy / Integration of Sources Weight: 5% Serious errors in the integration of sources, such as intentional or accidental plagiarism, or failure to use in-text citations. Sources are partially integrated using effective techniques of quoting, paraphrasing, and summarizing. Sources are mostly integrated using effective techniques of quoting, paraphrasing, and summarizing. Sources are consistently integrated using effective techniques of quoting, paraphrasing, and summarizing. The specific course learning outcomes associated with this assignment are: · Determine the best research methodology for a given educational research topic. · Conduct a literature review for a given research topic. · Describe ethical considerations in the research process. · Write an educational research proposal. · Interpret educational research results. Assignment 2: Research Paper – The Literature Review
  • 47. Due Week 5 and worth 200 points See the assignment overview here. For this assignment, you will create the second part of your research paper. The literature review should consist of a total of seven to ten (7-10) articles related to your research topic. These articles may include any articles you have previously found throughout this course. You should use the headings below for the sections of your paper. Write a three to five (3-5) page paper in which you: 1. Identify two to three (2-3) common themes in the literature. 2. Contrast the findings and results of the literature. 3. Identify gaps in the literature. 4. Summarize the literature as it relates to your topic. 5. Include seven to ten (7-10) peer-reviewed quantitative or qualitative articles related to your topic. Your assignment must follow these formatting requirements: • Be typed, double spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA format. Check with your professor for any additional instructions. • Include a cover page containing the title of the assignment, the student’s
  • 48. name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length. The specific course learning outcomes associated with this assignment are: • Conduct a literature review for a given research topic. 1 05 Histology Expected Learning Outcomes • Define the term histology. • List the four major tissue types. • Contrast the general features of the four major tissue types. • Classify the different types of epithelial tissues based on distinguishing structural characteristics. • Describe locations in the body where each type of epithelial tissue can be found. • Describe the functions of each type of epithelial tissue in the human body and correlate function with structure for each tissue type.
  • 49. • Classify the different types of connective tissues based on distinguishing structural characteristics • Describe locations in the body where each type of connective tissue can be found. • Describe functions of each type of connective tissue in the human body and correlate function with structure for each tissue type. • Compare and contrast the roles of individual cell types and fiber types within connective tissue. • Classify the different types of muscle tissues based on distinguishing structural characteristics and location in the body. • Describe functions of each type of muscle tissue in the human body and correlate function with structure for each tissue type. • Describe locations in the body where nervous tissue can be found. • Describe the structure and function of neurons and neuroglial cells in nervous tissue • Describe the structure and function of mucous, serous, and cutaneous membranes. • Describe locations in the body where each type of membrane can be found. • Distinguish between exocrine and endocrine glands, structurally and functionally.
  • 50. • Identify example locations in the body of exocrine and endocrine glands. • Classify the different kinds of exocrine glands based on structure and function. 2 Introduction • There are 50 trillion cells of 200 different cell types • Four broad categories of tissues • Epithelial tissue • Connective tissue • Nervous tissue • Muscular tissue • Histology (microscopic anatomy) - the study of tissues and how they are arranged into organs • Organ - structure with discrete boundaries that is composed of two or more tissue types The Study of Tissues 3
  • 51. The Primary Tissue Classes • Tissue - a group of similar cells and cell products working together to perform a specific role in an organ • The four primary tissues (epithelial, connective, nervous, and muscular) differ from each other in: • Types and functions of their cells • Characteristics of the matrix (extracellular material) • Relative amount of space occupied by cells versus matrix • Matrix (extracellular material) is composed of: • Fibrous proteins • Clear gel called ground substance • Also known as tissue fluid, extracellular fluid (ECF), interstitial fluid Interpreting Tissue Sections • Histologists preserve (fix), slice into thin sections one or two cells thick, and artificially colored with histological stains tissues • Some stains bind to different cellular components • Leads to ‘artifacts’ • Cell may be larger or smaller • Nucleus may be missing • Ducts might not look continuous 4
  • 52. Interpreting Tissue Sections • Longitudinal section (l.s.) • Tissue cut on its long axis • Cross section (c.s. or x.s.) or transverse section (t.s.) • Tissue cut perpendicular to long axis of organ • Oblique section • Tissue cut at angle between cross and longitudinal sections Epithelial Tissue 5 Epithelial Tissue • Epithelia are sheets of closely adhering cells, one or more cells thick • Covers body surfaces, lines body cavities, makes most glands • Functions vary • Protect deeper tissues from injury and infection • Produce and release chemical secretions • Excrete wastes • Absorb chemicals including nutrients • Selectively filter substances • Sense stimuli
  • 53. • Avascular (does not have blood vessels) • Usually nourished by underlying connective tissue • Between an epithelium and underlying connective tissue is Basement Membrane • Collagen, reticular proteins, glycoproteins, other protein- carbohydrate complexes that anchors to connective tissue below • Apical surface - surface of epithelial cell that faces away from the basement membrane • Basal surface - surface of epithelial cell facing the basement membrane • Cells closest to connective tissue usually have a high rate of mitosis Cell Shapes in Epithelial Tissue • Simple epithelia contain one layer of cells • Named by shape of cells • All cells touch basement membrane • Stratified epithelia contain more than one layer • Named by shape of apical cells • Some cells rest on top of others and do not touch basement membrane 6
  • 54. Simple Squamous Epithelium • Single row of thin cells • Locations: air sacs of lungs, some kidney tubules, lining of heart and blood vessels (endothelium), and serosa • Functions: Permits rapid diffusion or transport of substances, secretes serous fluid a: © McGraw-Hill Education/Dennis Strete, photographer Simple Cuboidal Epithelium • Single layer of square or round cells • Locations: Liver, thyroid, some glands, bronchioles, and most kidney tubules • Functions: Absorption and secretion of substances, mucus production 7 Simple Columnar Epithelium • Single row of tall, narrow cells with oval nuclei in basal half of cell • Often have microvilli (brush border) • Ciliated in some organs
  • 55. • May possess goblet cells • Locations: Lining of GI tract, uterus, kidney, and uterine tubes • Functions: Absorption and secretion of substances, mucus production Pseudostratified Epithelium • Looks multilayered, but all cells touch basement membrane • Nuclei at several layers • Often has cilia and goblet cells • Locations: Respiratory tract and portions of male urethra • Functions: Secretes and propels mucus 8 Keratinized Stratified Squamous Epithelium • Multiple cell layers; cells become flat and scaly toward surface • Locations: epidermis; palms and soles very heavily keratinized • Functions: Resists abrasion; retards water loss through skin; resists penetration by pathogenic organisms Non-keratinized Stratified Squamous Epithelium
  • 56. • Same as keratinized epithelium without surface layer of dead cells • Locations: Tongue, oral mucosa, esophagus, and vagina • Functions: Resists abrasion and penetration of pathogens 9 Stratified Cuboidal Epithelium • Two or more cell layers; surface cells square or round • Locations: Sweat gland ducts, ovarian follicles, and seminiferous tubules • Functions: Secretes sweat, produces sperm, produces ovarian hormones Transitional Epithelium • Multilayered epithelium with surface cells that change from round to flat when stretched • Locations: ureter and bladder • Functions: Allows for filling of urinary tract 10
  • 57. Connective Tissue Connective Tissue: Overview • Diverse, abundant type of tissue in which cells occupy less space than matrix • Supports, connects, and protects organs • Highly variable vascularity • Loose connective tissues have many blood vessels • Cartilage has few or no blood vessels • Functions of connective tissues vary • Connecting organs - tendons and ligaments • Support - bones and cartilage • Physical protection - bone • Immune protection - white blood cells attack foreign invaders • Movement - bones provide lever system • Storage - fat, calcium, phosphorus • Heat production - brown fat in infants • Transport – blood • Four categories: Fibrous, adipose, supportive, and fluid 11 1 - Fibrous Connective Tissue • Compos of Cells, Fibers, and Ground substance 1. Cells • Fibroblasts produce fibers and ground substance of matrix • Macrophages (from monocytes) phagocytize foreign
  • 58. material and activate immune system when they sense foreign matter (antigens) • Leukocytes (WBCs) • Neutrophils attack bacteria • Lymphocytes react against bacteria, toxins, and other foreign agents • Plasma cells (from lymphocytes) synthesize antibodies • Mast cells often found alongside blood vessels • Secrete heparin to inhibit clotting • Secrete histamine to dilate blood vessels • Adipocytes store triglycerides 1 - Fibrous Connective Tissue 2. Fibers • Collagenous fibers • Tough, flexible, and stretch-resisant • Tendons, ligaments, and deep layer of the skin are mostly collagen • Less visible in matrix of cartilage and bone • Reticular fibers • Thin collagen fibers coated with glycoprotein that form framework of spleen and lymph nodes as well as basement membrane • Elastic fibers • Thin, branching
  • 59. • Made of protein called elastin • Allows stretch and recoil 3. Ground Substance • Glycosaminoglycans (GAGs) • Long polysaccharides composed of amino sugars and uronic acid (disaccharides) • Regulate water and electrolyte balance of tissues • Chondroitin sulfate—most abundant GAG • Responsible for stiffness of cartilage • Other examples: heparin and hyaluronic acid • Proteoglycans • Gigantic molecules (core protein plus GAGs) shaped like bottle brushes • Form gravy-like colloids that hold tissues together • Adhesive glycoproteins • Protein-carbohydrate complexes • Bind components of a tissue together 12 Types of Fibrous Connective Tissue • Loose connective tissue • Much gel-like ground substance between cells • Types • Areolar
  • 60. • Reticular • Dense connective tissue • Fibers fill spaces between cells • Types vary in fiber orientation • Dense regular connective tissue • Dense irregular connective tissue Loose Connective Tissue: Areolar • Lots of seemingly empty space is ground substance • Possess all six cell types (Fibroblasts, Macrophages, Neutrophils, Lymphocytes, Plasma cells, Mast cells, and Adipocytes) • Fibers run in random directions • Mostly collagenous, but elastic and reticular also present • Found in tissue sections from almost every part of the body, surrounds blood vessels and nerves • Nearly every epithelium rests on a layer of areolar tissue • Blood vessels provide nutrition to epithelium and waste removal • Ready supply of infection-fighting leukocytes that move about freely in areolar tissue 13 Loose Connective Tissue: Reticular Tissue
  • 61. • Mesh of reticular fibers and fibroblasts • Found in lymph nodes, spleen, thymus, and bone marrow • Forms supportive stroma (framework) for lymphatic organs Dense Regular Connective Tissue • Densely packed, parallel collagen fibers • Only cell type is fibroblast with compressed nuclei • Found in tendons (attach muscles to bones) and ligaments (attach bones to bones) • Some ligaments have extra elastic fibers (elastic tissue) 14 Dense Irregular Connective Tissue • Densely packed, randomly arranged, collagen fibers and few visible cells • Withstands unpredictable stresses • Locations: deeper layer of skin; capsules around organs 2 - Adipose Tissue • Adipocytes are dominant cell type • Space between adipocytes is occupied by areolar tissue, reticular tissue, and blood capillaries
  • 62. • Adipose tissue is the body’s primary energy reservoir • Empty-looking cells due to large central globule of triglycerides • Nucleus pressed against cell membrane • Functions: Energy storage, insulation, cushioning • Brown fat of infants, children, and juveniles produces heat 15 3 - Supportive Connective Tissue: Cartilage • Stiff connective tissue with flexible matrix • Matrix rich in glycosaminoglycans and collagen fibers • Cells • Chondroblasts - cartilage cells that produce the matrix that will trap them • Chondrocytes - cartilage cells that are trapped in lacunae (cavities) • No blood vessels • Diffusion brings nutrients and removes wastes (thus heals slowly) • Wrapped with sheath of dense irregular connective tissue (perichondrium) with reserved chondroblasts • Except articular cartilage and fibrocartilage • Three types of cartilage
  • 63. • Hyaline cartilage, fibrocartilage, and elastic cartilage Hyaline Cartilage • Clear, glassy appearance because of fineness of collagen fibers • Eases joint movement, holds airway open, moves vocal cords, growth of juvenile long bones • Locations: Articular cartilage, costal cartilage, trachea, larynx, fetal skeleton 16 Elastic Cartilage • Cartilage containing abundance of elastic fibers • Provides flexible, elastic support • Locations: external ear and epiglottis Fibrocartilage • Cartilage containing large, coarse bundles of collagen fibers • Resists compression and absorbs shock
  • 64. • Lacks perichondrium • Locations: pubic symphysis, menisci, and intervertebral discs 17 3 - Supportive Connective Tissue: Bone • Bone (osseous) tissue is a calcified connective tissue • Bones of the skeleton are organs (made of bone tissue, cartilage tissue, marrow, and other tissue types) • Wrapped with periosteum (dense irregular connective tissue) • Osteocytes - mature bone cells within lacunae • Two forms of osseous tissue • Spongy bone: porous appearance • Delicate struts of bone (trabeculae) covered by compact bone • Found in heads of long bones and in middle of flat bones such as the sternum • Compact bone: denser, with no visible spaces • Arranged in cylinders that surround central (haversian) canals that run longitudinally through shafts of long bones • Blood vessels and nerves travel through central canal • Bone matrix deposited in concentric lamellae around each central canal • Osteon - central canal and its surrounding lamellae • Delicate canals (canaliculi) allow osteocytes in lacunae to
  • 65. contact each other 4 – Fluid Connective Tissue: Blood • Transports cells and dissolved matter from place to place • Plasma - blood’s ground substance • Formed elements - cells and cell fragments • Erythrocytes - red blood cells (RBCs): transport O2 and CO2 • Leukocytes - white blood cells (WBCs): defend against infection and disease • Neutrophils, eosinophils, basophils, lymphocytes, monocytes • Platelets - cell fragments involved in clotting 18 Nervous and Muscular Tissues - Excitable Tissues Nervous and Muscular Tissues—Excitable Tissues • Excitability - ability to respond to stimuli by changing membrane potential • Membrane potential - electrical charge difference (voltage) that occurs across the cell membrane • Developed to highest degree in nervous and muscular tissues • In nerve cells: changes in voltage result in rapid transmission of signals to other cells
  • 66. • In muscle cells: changes in voltage result in contraction, shortening of the cell 19 Nervous Tissue • Consists of neurons (nerve cells) • Detect stimuli • Respond quickly • Transmit coded information rapidly to other cells • Neuroglia (glial) • More numerous than neurons • Neuron parts • Neurosoma (cell body) • Houses nucleus and other organelles • Dendrites • Multiple short, branched processes • Receive signals from other cells • Transmit messages to neurosoma • Axon (nerve fiber) • Sends outgoing signals to other cells
  • 67. • Can be more than a meter long Muscular Tissue • Muscular tissue—elongated cells that are specialized to contract in response to stimulation • Primary job is to exert physical force on other tissues and organs • Creates movements involved in body and limb movement, digestion, waste elimination, breathing, speech, and blood circulation • Important source of body heat • Three types of muscle: skeletal, cardiac, and smooth 20 1 - Skeletal Muscle Tissue • Made of muscle fibers long thin cells • Most skeletal muscles attach to bone • Contains multiple nuclei adjacent to plasma membrane • Striations - alternating dark and light bands • Voluntary - conscious control over skeletal muscles Cardiac Muscle Tissue
  • 68. • Found only in wall of heart • Cardiomyocytes are branched, shorter than skeletal muscle fibers • Contain one centrally located nucleus • Intercalated discs join cardiomyocytes end to end • Provide electrical and mechanical connection • Striated and involuntary (not under conscious control) 21 Smooth Muscle Tissue • Made of fusiform myocytes lacking striations • Cells are relatively short and have one central nucleus • Involuntary function • Most is visceral muscle - making up parts of walls of hollow organs Cell Junctions, Glands, and Membranes 22 Cell Junctions • Most cells are
  • 69. anchored to each other or their matrix • Connections between cells - Cell Junctions • Four main types of cell junctions 1. Tight junctions 2. Desmosome 3. Hemidesmosome 4. Gap junction Tight Junctions • Tight junction—linkage between two adjacent cells by transmembrane cell-adhesion proteins • In epithelia, they form a zone that completely encircles each cell near its apical pole • Seals off intercellular space, making it difficult for substance to pass between cells 23 Desmosomes and Hemidesmosomes
  • 70. • Hook-like, J-shaped proteins arise from cytoskeleton • Anchor cytoskeleton to membrane plaque • Transmembrane proteins from each cell joined by cell adhesion proteins • Keeps cells from pulling apart—resist mechanical stress • Hemidesmosomes - half desmosomes that anchor basal cells of an epithelium to underlying basement membrane • Epithelium cannot easily peel away from underlying tissues Gap Junctions • Gap (communicating) junction formed by connexon proteins • Connexon form ring in membrane surrounding water filled pore • Located in cardiac and smooth muscle to allow ions to pass • Not found in skeletal muscle • Located in lens and cornea to allow nutrients to pass 24 Glands • Gland - cell or organ that secretes substances for use elsewhere in the body or releases them for elimination from the body
  • 71. • Usually composed of epithelial tissue in a connective tissue framework and capsule • Classified as • Exocrine glands - maintain their contact with surface of epithelium by way of a duct • Surfaces can be external (examples: sweat, tear glands) or internal (examples: pancreas, salivary glands) • Endocrine glands - have no ducts; secrete hormones directly into blood • Hormones: chemical messengers that stimulate cells elsewhere in the body • Examples: thyroid, adrenal, and pituitary glands • Some organs have both endocrine and exocrine functions • Examples: liver, gonads, pancreas • Unicellular glands – Secretory cell found in an epithelium that is predominantly nonsecretory • Can be exocrine or endocrine • Examples: mucus-secreting goblet cells in trachea or endocrine cells of stomach Exocrine Gland Structure
  • 72. • Capsule - connective tissue covering of exocrine gland • Septa or trabeculae: extensions of capsule that divide interior of gland into compartments (lobes and lobules) • Stroma—connective tissue framework of the gland • Supports and organizes glandular tissue • Parenchyma—cells that perform the tasks of synthesis and secretion • Typically cuboidal or simple columnar epithelium 25 Classification of Exocrine Glands by Structure • Duct shape: simple (unbranched) vs. compound (branched) • Gland shape • Tubular: narrow secretory portion • Acinar: secretory cells form dilated sac (acinus or alveolus) • Tubuloacinar: both tubular and acinar portions Classification of Exocrine Glands by Types of Secretions • Serous glands • Produce thin, watery secretions • Perspiration, milk, tears, digestive juices
  • 73. • Mucous glands • Produce glycoprotein, mucin, which absorbs water to form mucus • Goblet cells: unicellular mucous glands • Mixed glands • Contain both serous and mucous cell types and produce a mixture of the two types of secretions • Salivary glands produce this watery saliva for food digestion or thick saliva for protection 26 Classification of Exocrine Glands by Modes of Secretion • Merocrine secretion (used by eccrine glands) uses vesicles that release their secretion by exocytosis • Examples: tear glands, pancreas, gastric glands, and others • Apocrine secretion - lipid droplet covered by membrane and cytoplasm buds from cell surface • Mode of milk fat secretion by mammary gland cells • Note Apocrine sweat glands (in axillary region) are misnamed: use merocrine secretion
  • 74. • Holocrine secretion - cells accumulate a product until they disintegrate • Secrete a mixture of cell fragments and synthesized substances • Examples: oil glands of skin Membranes • Membranes may be only epithelial, only connective, or a mix of epithelial, connective, and muscular tissues • Examples of membranes of only connective tissue: dura mater, synovial membranes, periosteum • Examples of membranes of only epithelium: anterior surfaces of cornea and lens of eye • Cutaneous membrane (the skin)—largest membrane in the body • Stratified squamous epithelium (epidermis) resting on a layer of connective tissue (dermis) • Relatively dry layer serves protective function 27 Mucous and Serous Membranes • Mucous membrane (mucosa) lines passages that open to the external environment • Sublayers: epithelium, lamina
  • 75. propria (areolar tissue), muscularis mucosa (smooth muscle) • Absorptive, secretory, and protective functions • Often have mucus producing goblet cells • Serous membrane (serosa)— internal membrane • Simple squamous epithelium resting on a layer of areolar tissue • Produces serous fluid that arises from blood • Covers organs and lines walls of body cavities • Endothelium lines blood vessels and heart • Mesothelium lines body cavities (pericardium, peritoneum, and pleura) 1 3 Cellular form and function Expected Learning Outcomes • Identify the three main parts of a cell, and list the general
  • 76. functions of each. • Explain how cytoplasm and cytosol are different. • Describe how lipids are distributed in a cell membrane, and explain their functions. • Describe how carbohydrates are distributed in a cell membrane, and explain their functions. • Describe how proteins are distributed in a cell membrane, and explain their functions. • With respect to the following membrane transport processes – simple diffusion, facilitated diffusion, osmosis, active transport, exocytosis, endocytosis, phagocytosis, pinocytosis, & filtration: • State the type of material moving in each process. • Describe the mechanism by which movement of material occurs in each process. • Discuss the energy requirements and, if applicable, the sources of energy for each process. • Give examples of each process in the human body. • Describe the effects of hypertonic, isotonic, and hypotonic conditions on cells. • Demonstrate various cell transport processes and, given appropriate information, predict the outcomes of these demonstrations. • Define the term organelle. • For each different type of organelle associated with human
  • 77. cells: • Identify the organelle. • Describe the structure of the organelle. • Describe the function of the organelle 2 Introduction • All organisms are composed of cells • Cells are responsible for all structural and functional properties of a living organism • Important for understanding • Workings of human body • Mechanisms of disease Development of the Cell Theory • Cytology—scientific study of cells • Began when Robert Hooke coined the word cellulae to describe empty cell walls of cork in 17th century • Theodor Schwann concluded, about two centuries later, that all animals are made of cells • Louis Pasteur demonstrated in 1859 that “cells arise only from other
  • 78. cells” • Refuted idea of spontaneous generation—living things arising from nonliving matter • Cell theory • All organisms composed of cells and cell products • Cell is the simplest structural and functional unit of life • An organism’s structure and functions are due to activities of cells • Cells come only from preexisting cells • Cells of all species exhibit biochemical similarities 3 Cell Shapes and Sizes • About 200 types of cells in human body with varied shapes • Squamous—thin, flat, scaly • Cuboidal—squarish-looking • Columnar—taller than wide • Polygonal—irregularly angular shapes, multiple sides • Stellate—star-like • Spheroid to ovoid—round to oval
  • 79. • Discoid—disc-shaped • Fusiform—thick in middle, tapered toward the ends • Fibrous—thread-like • Note: A cell’s shape can appear different if viewed in a different type of section (longitudinal vs. cross section) The Relationship Between Cell Surface Area and Volume • Most cells about 10–15 micrometers (μm) in diameter • Egg cells (very large) 100 μm diameter • Some nerve cells over 1 meter long • Limit on cell size: an overly large cell cannot support itself, may rupture • For a given increase in diameter, volume increases more than surface area • Volume proportional to cube of diameter • Surface area proportional to square of diameter Large cell Diameter = 20 μm Surface area = 20 μm × 20 μm × 6 = 2,400 μm2 Volume = 20 μm × 20 μm × 20 μm = 8,000 μm3
  • 80. Small cell Diameter = 10 μm Surface area = 10 μm × 10 μm × 6 = 600 μm2 Volume = 10 μm × 10 μm × 10 μm = 1,000 μm3 Effect of cell growth: Diameter (D) increased by a factor of 2 Surface area increased by a factor of 4 (= �2) Volume increased by a factor of 8 (= �3) 4 Basic Components of a Cell • Plasma (cell) membrane • Surrounds cell, defines boundaries • Made of proteins and lipids • Cytoplasm • Organelles • Cytoskeleton • Inclusions • Cytosol (intracellular fluid, ICF) • Extracellular fluid (ECF) • Fluid outside of cells
  • 81. includes tissue (interstitial) fluid The Plasma Membrane • Has intracellular and extracellular faces • Functions • Defines cell boundaries • Governs interactions with other cells • Controls passage of materials in and out of cell • 98% of membrane molecules are lipids • 75% phospholipids • Amphipatic molecules arranged in a bilayer • Hydrophilic phosphate heads face water on each side of membrane • Hydrophobic tails—are directed toward the center, avoiding water • Drift laterally, keeping membrane fluid • 20% Cholesterol • Can both holds phospholipids still and stiffen membrane or prevent close packing and make membrane more flexible
  • 82. • 5% Glycolipids • Phospholipids with short carbohydrate chains on extracellular face • Contributes to glycocalyx—carbohydrate coating on cell surface 5 The Plasma Membrane • 2% of the molecules but 50% of the weight of membrane are protein • Integral proteins—penetrate membrane • Transmembrane proteins pass completely through • Hydrophilic regions contact cytoplasm, extracellular fluid • Hydrophobic regions pass through lipid of the membrane • Some drift in membrane; others are anchored to cytoskeleton • Peripheral proteins
  • 83. • Adhere to one face of the membrane (do not penetrate it) • Usually tethered to the cytoskeleton Some Functions of Membrane Proteins 6 The Glycocalyx • Fuzzy coat external to plasma membrane • Carbohydrate moieties of glycoproteins and glycolipids • Unique in everyone but identical twins • Functions • Physical Protection • Self Identification (e.g. in immunity or transplant compatibly) • Cell adhesion Extensions of Cell Surface: Microvilli
  • 84. • Extensions of membrane (1–2 μm) • Gives 15 to 40 times more surface area • Best developed in cells specialized in absorption • On some absorptive cells they are very dense and appear as a fringe— “brush border” 7 Extensions of Cell Surface: Cilia • Cilia—hairlike processes 7–10 μm long • Single, nonmotile primary cilium found on several cells such as • Balance cells in inner ear • Motile cilia—respiratory tract, uterine tubes, ventricles of brain, ducts of testes • 50 to 200 on each cell • Beat in waves sweeping material across a surface in one direction • Power strokes followed by recovery strokes Extensions of Cell Surface: Cilia
  • 85. • Axoneme—core of motile cilium • Has 9 + 2 structure of microtubules • “Grows” from basal body • Uses energy from ATP 8 Extensions of Cell Surface: Flagella and Pseudopod • Tail of a sperm—only functional flagellum in humans • Whip-like structure with axoneme identical to cilium’s • Much longer than cilium • Movement is undulating, snake-like, corkscrew • No power stroke and recovery strokes • Pseudopods—continually changing extensions of the cell that vary in shape and size • Can be used for cellular locomotion, capturing • foreign particles Membrane Transport
  • 86. 9 Membrane Transport • Plasma membrane is selectively permeable—allowing some things through, but preventing others from passing • Passive mechanisms require no ATP • Random molecular motion of particles provides necessary energy • Filtration, diffusion, osmosis • Active mechanisms consume ATP • Active transport and vesicular transport • Carrier-mediated mechanisms use a membrane protein to transport substances across membrane Filtration • Filtration—particles are driven through membrane by physical pressure • Examples • Filtration of water and small solutes through gaps in capillary walls • Allows delivery of water
  • 87. and nutrients to tissues • Allows removal of waste from capillaries in kidneys 10 Simple Diffusion • Simple diffusion—net movement of particles from place of high concentration to place of lower concentration • Due to constant, spontaneous molecular motion • Molecules collide and bounce off each other • Substances diffuse down their concentration gradient • Does not require a membrane • Substance can diffuse through a membrane if the membrane is permeable to the substance • Factors affecting diffusion rate through a membrane • Molecular weight: larger molecules move slower • Osmosis • Osmosis—net flow of water through a selectively permeable membrane
  • 88. • Water moves from the side where it (water) is more concentrated to the side where it is less concentrated • Solute particles that cannot pass through the membrane “draw” water from the other side • Water can diffuse through phospholipid bilayers, but osmosis is enhanced by aquaporins—channel proteins in membrane specialized for water passage • Cells can speed osmosis by installing more aquaporins • Osmotic pressure—hydrostatic pressure required to stop osmosis • Increases as amount of nonpermeating solute rises • Reverse osmosis—process of applying mechanical pressure to override osmotic pressure • Allows purification of water (a) Start (b) 30 minutes later 11
  • 89. Osmolarity and Tonicity • One osmole (osm) = 1 mole of dissolved particles • Takes into account whether solute ionizes in water • 1 M glucose is 1 osm/L • 1 M NaCl is 2 osm/L • Osmolarity—number of osmoles per liter of solution • Body fluids contain a mix of many chemicals, and osmolarity is the total osmotic concentration of all solutes • Blood plasma, tissue fluid, and intracellular fluid are 300 milliosmoles per liter (mOsm/L) • Tonicity—ability of a surrounding solution to affect fluid volume and pressure in a cell • Depends on concentration of nonpermeating solutes • Hypotonic solution • Hypertonic solution • Isotonic solution (a) Start
  • 90. (b) 30 minutes later Effects of Tonicity on RBCs • Hypotonic solution—causes cell to absorb water and swell • Has a lower concentration of nonpermeating solutes than intracellular fluid (ICF) • Distilled water is an extreme example • Hypertonic solution—causes cell to lose water and shrivel (crenate) • Has a higher concentration of nonpermeating solutes than ICF • Isotonic solution—causes no change in cell volume • Concentrations of nonpermeating solutes in bath and ICF are the same • Normal saline (0.9% NaCl) is an example 12 Carrier-Mediated Transport • Transport proteins in membrane carry solutes into or out of cell (or organelle) • Specificity • Transport proteins are specific for particular solutes • Solute (ligand) binds to receptor site on carrier protein • Solute is released unchanged on other side of membrane • Three kinds of carriers 1. Uniport—carries one type of solute
  • 91. • Example: Calcium pump 2. Symport—carries two or more solutes simultaneously in same direction (cotransport) • Example: sodium-glucose transporters 3. Antiport—Carries two or more solutes in opposite directions (countertransport) • Example: sodium-potasium pump removes Na+, brings in K+ • Three mechanisms of carrier-mediated transport • Facilitated diffusion, primary active transport, secondary active transport Facilitated diffusion • Carrier moves solute down its concentration gradient • Does not consume ATP • Solute attaches to binding site on carrier, carrier changes conformation, then releases solute on other side of membrane 13 Primary active transport • Carrier moves solute through a membrane up its concentration gradient • The carrier protein uses ATP for energy
  • 92. • Examples: • Calcium pump (uniport) uses ATP while expelling calcium from cell to where it is already more concentrated • Sodium–potassium pump (antiport) uses ATP while expelling sodium and importing potassium into cell • Each pump cycle consumes one ATP and exchanges three Na+ for two K+ • Keeps K+ concentration higher and Na+ concentration lower within the cell than in ECF • Necessary because Na+ and K+ constantly leak through membrane • Half of daily calories utilized for Na+−K+ pump • Why? • Regulates solute concentration and thus osmosis and thus cell volume • Maintains negatively charged resting membrane potential • Maintains steep Na+ concentration gradient allowing for secondary active transport Secondary active transport
  • 93. • Carrier moves solute through membrane but only uses ATP indirectly • Example: sodium-glucose transporter (SGLT) (symport) • Moves glucose into cell while simultaneously carrying sodium down its gradient • Depends on the primary transport performed by Na+- K+pump • Does not itself use ATP • Prevents loss of glucose to urine 14 Vesicular Transport • Moves large particles, fluid droplets, or numerous molecules at once through the membrane in vesicles—bubble-like enclosures of membrane • Endocytosis—vesicular processes that bring material into cell • Pinocytosis—“cell drinking,” taking in droplets of ECF containing molecules useful in the cell
  • 94. • Membrane caves in, then pinches off pinocytic vesicle • Phagocytosis - engulfing large particles using pseudopods creating phagosome • Receptor-mediated endocytosis— particles bind to specific receptors on plasma membrane • Clathrin-coated vesicle • Exocytosis—discharging material from the cell Exocytosis and Transcytosis • Exocytosis—discharging material from the cell • Transcytosis • Transport of material across the cell by capturing it on one side and releasing it on the other • Receptor-mediated endocytosis moves it into the cell and exocytosis moves it out the other side 15 The Cell Interior
  • 95. The Cytoskeleton • Network of protein filaments and cylinders • Composed of: microfilaments, intermediate fibers, microtubules • Microfilaments • 6 nm thick • Made of actin protein • Forms terminal web under p.m. • Intermediate filaments • 8–10 nm thick • Within skin cells, made of protein keratin • Give cell shape, resist stress • Microtubules • 25 nm thick • Consist of protofilaments made of protein tubulin • Radiate from centrosome; can come and go • Maintain cell shape, hold organelles, act as railroad tracks for walking motor proteins, make axonemes of cilia and flagella, form mitotic spindle 16
  • 96. Organelles • Internal structures of a cell, carry out specialized metabolic tasks • Membranous organelles • Nucleus, mitochondria, lysosomes, peroxisomes, endoplasmic reticulum, and Golgi complex • Nonmembranous organelles • Ribosomes, centrosomes, centrioles, basal bodies The Nucleus • Largest organelle (5 μm in diameter) • Most cells have one nucleus • A few cell types are anuclear or multinucleate • Nuclear envelope—double membrane around nucleus • Perforated by nuclear pores formed by rings of proteins • Regulate molecular traffic through envelope • Hold the two membrane layers together • Nuclear envelope is supported by nuclear lamina
  • 97. • Web of protein filaments • Provides points of attachment for chromatin • Helps regulate cell life cycle • Nucleoplasm—material in nucleus • Chromatin (thread-like) composed of DNA and protein • Nucleoli—masses where ribosomes are produced 17 Endoplasmic Reticulum • System of channels (cisternae) enclosed by membrane • Rough endoplasmic reticulum— parallel, flattened sacs covered with ribosomes • Continuous with outer membrane of nuclear envelope • Produces phospholipids and proteins of the plasma membrane • Synthesizes proteins that are packaged in other organelles or secreted from cell
  • 98. • Smooth endoplasmic reticulum • Lack ribosomes • Cisternae more tubular and branching • Synthesizes steroids and other lipids • Detoxifies alcohol and other drugs • Calcium storage • Rough and smooth ER are functionally different parts of the same network Ribosomes • Ribosomes—small granules of protein and RNA • Found in nucleoli, in cytosol, and on outer surfaces of rough ER, and nuclear envelope • They “read” coded genetic messages (messenger RNA) and assemble amino acids into proteins specified by the code 18 Golgi Complex • System of cisternae that
  • 99. synthesizes carbohydrates and puts finishing touches on protein synthesis • Receives newly synthesized proteins from rough ER • Sorts proteins, splices some, adds carbohydrate moieties to some, and packages them into membrane-bound Golgi vesicles • Some vesicles become lysosomes • Some vesicles migrate to plasma membrane and fuse to it • Some become secretory vesicles that store a protein product for later release Lysosomes and Peroxisomes • Lysosomes - Package of enzymes bound by a membrane • Functions • Intracellular hydrolytic digestion of proteins, nucleic acids, complex carbohydrates, phospholipids, and other substances • Autophagy—digestion of cell’s surplus organelles • Autolysis—“cell suicide”: digestion of a surplus cell by itself • Peroxisomes - Resemble lysosomes but contain different enzymes and are produced by endoplasmic reticulum
  • 100. • Function is to use molecular oxygen to oxidize organic molecules • Neutralize free radicals, detoxify alcohol, other drugs, and a variety of blood- borne toxins • Break down fatty acids into acetyl groups for mitochondrial use in ATP synthesis • Reactions produce hydrogen peroxide H2O2 • Catalase breaks down excess peroxide to H2O and O2 • In all cells, but abundant in liver and kidney 19 Proteasomes • Proteasomes—hollow, cylindrical organelle that disposes of surplus proteins • Contain enzymes that break down tagged, targeted proteins into short peptides and amino acids Mitochondria • Specialized for synthesizing ATP • Surrounded by a double membrane • Inner membrane has folds
  • 101. called cristae • Spaces between cristae called matrix • Matrix contains ribosomes, enzymes used for ATP synthesis, small circular DNA molecule • Mitochondrial DNA (mtDNA) • “Powerhouses” of the cell • Energy is extracted from organic molecules and transferred to ATP 20 Centrioles • Short cylindrical assembly of microtubules arranged in nine groups of three microtubules each • Two centrioles lie perpendicular to each other within the centrosome—small clear area in cell • Play important role in cell division
  • 102. • Form basal bodies of cilia and flagella • Each basal body is a centriole that originated in centriolar organizing center and then migrated to the membrane Inclusions • Stored cellular products • Glycogen granules, pigments, and fat droplets 1 A General Orientation to Human Anatomy Expected Learning Outcomes • Describe a person in anatomical position. • Describe how to use the terms right and left in anatomical reference. • Identify the various planes in which a body might be dissected. • Describe the appearance of a body presented along various planes. • Describe the location of the body cavities and identify the major organs found in
  • 103. each cavity. • List and describe the location of the major anatomical regions of the body. • Describe the location of the four abdominopelvic quadrants and the nine abdominopelvic regions and list the major organs located in each. • List and define the major directional terms used in anatomy. • Describe the location of body structures, using appropriate directional terminology. • Describe the location of structures of the body, using basic regional and systemic terminology. • List the organ systems of the human body and their major components. • Describe the major functions of each organ system. 2 Anatomical Position • Upright, feet flat on floor, palms forward • Left vs. Right
  • 104. Directional Terms 3 Anatomical Planes • Sagittal – divides the body into right and left parts • Midsagittal or median – sagittal plane that lies on the midline • All others parasagittal • Frontal or coronal – divides the body into anterior and posterior parts • Transverse or horizontal – divides the body into superior and inferior parts Major Body Regions • Axial Region • Head • Neck (cervical region) • Trunk • Thoracic Region • Abdominal Region
  • 105. • Appendicular Region • Upper limb • Lower Limbs 4 Further Division of the Abdominal Region • Two methods • Four Quadrants • Nine regions Body Cavities 5 Membranes of Body Cavities • Cranial cavity and vertebral canal lined by three layer meninges • Thoracic cavity has double layer serous membranes with lubrication serous fluid • Parietal and visceral pericardium create pericardial cavity with pericardial fluid • Two parietal and visceral pleura create pleural cavity with pleural fluid
  • 106. Membranes of Body Cavities • Abdominopelvic cavity has double layer serous membranes • Parietal and visceral peritoneum create peritoneal cavity with peritoneal fluid • Some organs are intraperitoneal • Surrounded by peritoneum and connected to posterior by mesenteries • Some organs are retroperitoneal 6 The Human Organ Systems 1 1 Major Themes of Anatomy and physiology Expected Learning Outcomes • Define the terms anatomy and physiology. • Give specific examples to show the interrelationship between anatomy and physiology. • Describe, in order from simplest to most complex, the major levels of organization in the human organism.
  • 107. • Give an example of each level of organization. • Define homeostasis • List the components of a feedback loop and explain the function of each. • Compare and contrast positive and negative feedback in terms of the relationship between stimulus and response. • Explain why negative feedback is the most commonly used mechanism to maintain homeostasis in the body. • Provide an example of a negative feedback loop that utilizes the nervous system to relay information. Describe the specific organs, structures, cells or molecules (receptors, neurons, CNS structures, effectors, neurotransmitters) included in the feedback loop. • Provide an example of a negative feedback loop that utilizes the endocrine system to relay information. Describe the specific cells or molecules (production cells, hormones, target cells) included in the feedback loop. • Provide an example of a positive feedback loop in the body. Describe the specific structures (organs, cells or molecules) included in the feedback loop. • Provide specific examples to demonstrate how organ systems respond to maintain homeostasis • Explain how different organ systems relate to one another to maintain homeostasis • Predict factors or situations affecting various organ systems
  • 108. that could disrupt homeostasis. • Predict the types of problems that would occur in the body if various organ systems could not maintain homeostasis and allowed regulated variables (body conditions) to move away from normal. 2 Anatomy—The Study of Form • Examining structure of the human body • Inspection • Palpation – feeling with fingertips • Auscultation – listening to normal body sounds • Percussion – tapping and then listening to resulting sounds • Cadaver dissection • Cutting and separating human body tissues to reveal tissue relationships • Comparative anatomy • Study of multiple species to learn about form and evolution • Exploratory surgery • Medical imaging • Viewing the inside of the body without surgery • Radiology—branch of medicine concerned with imaging • Gross anatomy • Study of structures that can be seen with the naked eye • Histology
  • 109. • Examination of tissues with microscope • Histopathology • Microscopic examination of tissues for signs of disease • Cytology • Study of structure and function of cells Anatomical Variation • Anatomy books show most common organization of structures • Some individuals lack certain muscles • Some individuals have an atypical number of vertebrae • Some individuals have an atypical number of certain organs (for example, kidneys) • Some individuals (1 in 8000) show situs inversus - left-right reversal of organ • https://www.anatomyatlases.org/AnatomicVariants/AnatomyHP. shtmlnt 3 Physiology—The Study of Function • Subdisciplines • Neurophysiology (physiology of nervous system)
  • 110. • Endocrinology (physiology of hormones) • Pathophysiology (mechanisms of disease) • Comparative physiology • Study of different species to learn about body functions • Basis for much of our understanding of human physiology and the development of new drugs and medical procedures The Hierarchy of Complexity • Reductionism—large, complex systems can be understood by studying their simpler components • Essential to scientific thinking • Holism—“emergent properties” of the whole organism cannot be predicted from the properties of the separate parts • Humans are more than the sum of their parts 4 The Hierarchy of Complexity • Organism composed of organ systems • Organ systems composed of organs • Organs composed of tissues
  • 111. • Tissues composed of cells • Cells composed of organelles • Organelles composed of molecules • Molecules composed of atoms Homeostasis and Negative Feedback • Homeostasis—the ability to detect change, activate mechanisms that oppose it, and thereby maintain relatively stable internal conditions • Claude Bernard (1813–78) • Noted fairly constant internal conditions despite changing external conditions (for example, temperature) • Walter Cannon (1871–1945) • Coined the term homeostasis • Negative feedback allows for dynamic equilibrium within a limited range around a set point • The body senses a change and “negates” or reverses it • Loss of homeostatic control causes illness or death 5
  • 112. Negative Feedback in Thermoregulation Homeostasis and Negative Feedback • Because feedback mechanisms alter the original changes that triggered them, they are called feedback loops. • Homeostasis in body temperature • If too warm, vessels dilate in the skin and sweating begins (heat-losing mechanism) • If too cold, vessels in the skin constrict and shivering begins (heat-gaining mechanism) 6 Homeostatic Compensation for a Postural Change in Blood Pressure • Receptor—structure that senses change in the body (e.g., stretch receptors above heart that monitor blood pressure) • Integrating (control) center— control center that processes the sensory information, “makes a decision,” and directs the response (e.g., cardiac center of the brain)
  • 113. • Effector— cell or organ that carries out the final corrective action to restore homeostasis (e.g., the heart) Homeostatic Compensation for Blood Calcium Levels • Ca2+ levels need to be maintained at 9.2 – 10.4 mg/dL for proper nervous and muscle funtion • Parathyroid hormone (PTH) secreted by parathyroid glands on posterior surface of thyroid when calcium levels low in blood • PTH raises calcium blood level by four mechanisms 1. Stimulates osteoclast and bone resorption 2. Inhibits osteoblasts and bone deposition 3. Promotes calcium reabsorption by kidneys, so less lost in urine 4. Promotes phosphate excretions by kidneys, so less bone deposition Figure 7.16b
  • 114. 7 Positive Feedback and Rapid Change • Self-amplifying cycle • Leads to greater change in the same direction • Feedback loop is repeated—change produces more change • Normal way of producing rapid changes • Examples include: childbirth, blood clotting, protein digestion, and generation of nerve signals • Can sometimes be dangerous • Example Heat Shock • Body temperature above 40C (104˚F) increases speed of chemical reactions, increasing heat • Which increase the speed of reactions • Which increase heat • Until death at 45C (113˚F) Positive Feedback in Childbirth