Cells and their_functions1
- 1. Cells and Their Functions
- 2. What is a cell?
- 3. Here’s what a “cell” is! Cell - the smallest unit of an organism that carries on the functions of life A cell can perform all the processes of life .
- 4. Comparing cells Many Sizes: nerve cells - up to a meter long human egg cell - dot of an i bacteria - 80,000 could fit in the dot of an i
- 5. Comparing cells Different shapes: Related to their function (job)
- 6. Comparing cells Cell types: Prokaryotic cell – very simple; no membrane-bound structures (ex: bacteria ) Eukaryotic cell – more advanced; has membrane- bound structures (ex: animal cells, plant cells)
- 7. Early Cell Scientists Robert Hooke (1665) An English scientist who looked at slices of cork under a crude compound microscope and saw “a great many little boxes ” that he called “cells.” First person to see cells. “ Cell” comes from the Latin word for “ little room .”
- 8. Early Cell Scientists Anton van Leeuwenhoek (1673) A Dutch shopkeeper who looked at pond water using a simple microscope and saw what he called “ animalcules .” Today, we call them single-celled organisms . An Early Simple Microscope
- 9. Early Cell Scientists Matthias Schleiden (1838) A German botanist who discovered that all plants are made up of similar units , or cells.
- 10. Early Cell Scientists Theodor Schwann (around 1830) A German scientist who stated that all plants and animals are made up of building blocks , or cells. He also observed that there are similarities and differences between plant and animal cells.
- 11. Early Cell Scientists Rudolph Virchow (1858) This German physician also reported that every living thing is made of up vital units, known as cells . He also predicted that cells come from other cells .
- 12. Cell Theory 1. All living things are made up of one or more cells . 2. Cells are the basic unit of structure and function in living things. 3. All cells come only from other living cells.
- 13. Cell Structure Animal Cell Plant Cell
- 14. Cell Structure A cell is like a small town : Different parts have different and specialized jobs . Plant cells and animal cells have many similar structures, but have several important differences .
- 15. Cell Membrane Structure : Outer boundary of the cell Phospholipid bilayer membrane Selectively permeable
- 16. Cell Membrane Function (job) : Protects inside Supports/gives shape Controls what enters/leaves - “gatekeeper” Helps maintain homeostasis (ability to keep a stable environment)
- 17. Cell Wall Structure : ONLY IN PLANTS Made of cellulose Strong & rigid Dead layer
- 18. Cell Wall Function (job) : Protects/ supports Gives shape
- 19. Cytoplasm Structure : Jelly-like substance 80 % water
- 20. Cytoplasm Function (job) : Organelles float in cytoplasm Materials for growth are found in cytoplasm Expels waste through cell membrane
- 21. Nucleus Structure : Surrounded by nuclear membrane Usually round/oval Near center
- 22. Nucleus Function (job) : Control center of cell Controls cell activities Contains chromosomes
- 23. Mitochondria Structure : Has an outer membrane and an inner folded membrane Rod shaped
- 24. Mitochondria Function (job) : Cellular respiration Turns food into useable energy (ATP)
- 25. Ribosomes Structure : Tiny, round, dark Can be free floating or attached to endoplasmic reticulum
- 26. Ribosomes Function (job) : Protein factories Assembles proteins used in growth, repair and control
- 27. Endoplasmic Reticulum Structure : Network of tubes and canals Smooth ER - no ribosomes attached Rough ER - ribosomes are attached
- 28. Endoplasmic Reticulum Function (job) : Transports materials “intracellular highway”
- 29. Golgi Bodies Structure : Series of flattened sacs
- 30. Golgi Bodies Function (job) : Processes, packages and secretes material Materials that are transported by the ER usually stop first at the Golgi bodies where they are stored or altered before moving to other parts of the cell
- 31. Lysosomes Structure : ONLY IN ANIMAL CELLS Contains powerful digestive chemicals
- 32. Lysosomes Function (job) : Contains digestive enzymes (chemicals), breaks things down “ suicide sac”
- 33. Vacuoles Structure : Fluid -filled sacs that float in the cytoplasm
- 34. Vacuoles Function (job) : Stores water and food materials Stores waste and helps the cell get rid of waste Plant cells contain a large central vacuole - filled with water - helps give shape
- 35. Chloroplast Structure : ONLY IN PLANT CELLS Green, oval-shaped Contains green pigment chlorophyll
- 36. Chloroplast Function (job) : Site of photosynthesis Traps the sun’s energy to make glucose
- 38. How are plant and animal cells different? PLANT CELLS: Have cell walls , chloroplasts , large vacuoles
- 39. How are plant and animal cells different? ANIMAL CELLS: Have lysosomes
- 40. How are different cells adapted to their functions? Muscle Cells: Have large quantities of mitochondria for energy. Plant Cells: Rigid cell walls allow plants to grow upright .
- 41. How are different cells adapted to their functions? Red Blood Cells: Thin, flexible discs allow them to squeeze through tiny blood vessels . Nerve Cells: Have long projections through which message s are sent throughout the body.
- 42. Vocabulary Permeable Diffusion Osmosis Mitosis Chromosome Centriole Centromere
- 43. Organization of Living Things
- 44. Organization of Living Things Five main levels of organization 1. Cell 2. Tissue 3. Organ 4. Organ System 5. Organism
- 45. Tissue Example: Muscle Tissues are made of specialized cells.
- 46. Organ Examples: Heart, Lung, Brain Found in both plants and animals. Composed of tissue that is organized into groups that work together to perform special functions.
- 47. Organ System Example: Circulatory System A group of organs that work together.
- 48. 10 Organ Systems in complex organisms (humans, dogs, birds, etc.) 1. Circulatory 2. Digestive 3. Nervous 4. Respiratory 5. Skin 6. Skeletal 7. Muscular 8. Reproductive 9. Excretory 10. Endocrine
- 49. ORGANISMS Different organ systems work together to keep the organism alive.
- 50. QUESTION: Classify the following as a tissue, organ, or organ system. a. Brain, spinal cord, and nerves b. Heart c. Group of muscle cells
- 51. QUESTION: Can a single-celled organism contain tissue? Explain.
- 52. QUESTION: Give one example of each: a. Cell c. Tissue b. Organ d. Organism