Macromolecules and enzymes ppt notes
- 1. Unit 2: Macromolecules & Enzymes Textbook Source: Chapter 6 Section 2 and 4 1
- 2. LEARNING OBJECTIVES FOR UNIT 2 • To describe the basic molecular structure AND functions of carbohydrates, lipids, proteins, and nucleic acids. • To explain how enzymes speed up the rate of a biochemical reaction by lowering the activation energy. • To describe the effect of environmental factors (pH and temperature) on enzyme activity. 2
- 3. Organic Compounds • Are compounds that contain CARBON • Macromolecules are LARGE organic molecules (aka polymers) 3
- 4. FUNCTIONAL GROUPS Functional groups are collections of atoms in a molecule that participate in characteristic chemical reactions. You will notice them in the structures of the four main macromolecules that we will study in this unit. 4
- 5. Macromolecules • Four essential macromolecules are: 1.Carbohydrates 2.Lipids 3.Proteins 4.Nucleic acids • Made up of smaller “building blocks” called MONOMERS. 5
- 6. Dehydration Synthesis: • Process that links monomers into polymers. • Hydrolysis is the opposite process. 6
- 7. The Four Essential Macromolecules for Life 7
- 8. 1. Carbohydrates Components: C, H, O Monomer = Monosaccharide (1 sugar unit) Function: • Mainly used for energy! • Make plant cell wall (ex.cellulose) Structure: ring formation Ex: glucose (C6H12O6) glucose 8
- 11. Different types of Carbs. • Simple sugars: provide energy but some lack vitamins, minerals & fiber (ex. candy) a) Monosaccharides Ex. Glucose (corn sugar) Ex. Fructose (fruit sugar) b) Disaccharide Ex. saccharose (cane sugar) Ex. Lactose (milk sugar) • Complex sugars: provides vitamins minerals, & fiber a) Polysaccharides in plants: starch & cellulose b) Polysaccharides in animals: glycogen 11
- 12. 12
- 13. Examples of Polysaccharides 13
- 14. 2. Lipids Components: C, H, O Functions: • Energy storage • Insulation • Make up cell membranes Ex: Fats, oils, steroids, hormones, phospholipids Structure: long carbon chains or many rings linked together (ex. steroids) 14
- 15. Components of a lipid: 1 glycerol and 3 fatty acids. 15 Teacher’s Notes: •Hydrophobic molecule (“water fearing”) •Will NOT dissolve in water •Nonpolar
- 16. TYPES OF STEROIDS: 1) HORMONES 2) CHOLESTEROL 16 Teacher’s Notes: Steroid hormones help control metabolism, inflammation, immune functions, salt and water balance, development of sexual characteristics, and the ability to withstand illness and injury. The term steroid describes both hormones produced by the body and artificially produced medications that duplicate the action for the naturally occurring steroids.
- 17. ANABOLIC STEROIDS: Teacher’s Notes: • Anabolic steroids are available legally only by prescription, to treat conditions that occur when the body produces abnormally low amounts of testosterone, such as delayed puberty and some types of impotence. They are also prescribed to treat body wasting in patients with AIDS and other diseases that result in loss of lean muscle mass. • Anabolic steroids are being abused by some athletes and others to enhance performance or improve physical appearance. 17
- 18. Structure of a Phospholipid 18
- 19. Structure of Phospholipid 19
- 20. 3. Proteins (Polypeptides) • Components: C, H, O, N • Monomer = Amino acids • Structure: always has a NH2 , and COOH group • Amino acids peptide chains proteins • Are assembled in the ribosome of the cell. 20 Teacher’s Note: Ribosomes are the cell’s protein factories.
- 21. Functions of Proteins • Make up structures (ex. fur, nails, muscles) • Defend against foreign substances (ex. Antibodies) • Transport (ex. Hemoglobin) • Cellular signaling (ex. Hormones) • Make up ENZYMES 21
- 22. Structure of an Amino Acid 22 amino There are 20 amino acids with a different R replaceable group giving each one very unique chemical properties
- 23. Examples of Amino Acids 23
- 24. Levels of Protein Structure 24
- 25. ENZYMES: • Speed up the rate of chemical reactions by weakening bonds thus lowering the activation energy to start a reaction. • Activation energy: It’s the required energy for a reaction to occur. 25
- 26. Lowering the Activation Energy Teacher’s Notes: When enzymes are present, the cell spends less energy to start a chemical reaction. 26
- 27. Example of a Chemical Reaction in the presence of an Enzyme 27
- 28. How do enzymes work? 28
- 29. Enzyme-Substrate Complex: A substrate (a reactant): • fits into the active site like a key in a lock (known as the “Lock & Key Model”) • It is specific to an enzyme 29 Substrate Enzyme Joins Teacher’s notes: Thousands of different enzymes exist in the body.
- 30. Enzymes: • Can be re-used • Can reach saturation. 30 Teacher’s Notes: Saturation means that all of the enzyme molecules are occupied with substrate. Adding more substrate will not increase the rate of reaction because the enzymes are already working at full capacity. If an enzyme is unsaturated (not all molecules are busy with substrate), than adding more substrate will increase the reaction rate, because more enzyme molecules can be working.
- 31. INHIBITORS: 31
- 32. What can destroy an enzyme? Changes in: • pH • Salt concentration • Temperature Once denatured (destroyed) it can’t function properly. 32
- 33. Denaturing a Protein Teacher’s Notes: Cooking an egg is an example of 33 denaturing a protein (notice the change in the egg whites)
- 34. 4. Nucleic acids Components: C, H, O, N, P Two types: DNA, RNA Monomer = nucleotide Function: • Holds & transfer information • Codes for proteins. Structure: single or double stranded 34
- 35. DNA is made of many “nucleotides” 35
- 38. Activity: Identifying Macromolecules Activity Part A: Identify the macromolecules labeled A-I Part B: Look at the data table with the information on Samples 1 -5 1)Which samples are macromolecules? 2) What type of macromolecules are they? Part C: Answer Q1-15 in your notebooks 38
- 39. Part A: Classify the following macromolecules. A. B. C. D. E. F. G. Tip: R means “replaced”. It is not an element.
- 40. Part A: Classify the following macromolecules (CONT.) H. I. Hint: You should get (3) carbs, (1) protein, (3) lipids and (2) nucleic acids
- 41. Part B: Look at the data table 2. Identify the samples that have macromolecules AND to what category they belong to (carbs, proteins, lipids, or nucleic acids) Data Table 2 Samples 1 2 3 4 5 Ar N Ne O Cl H C P Hint: In order to be a macromolecule it has to have one of these combinations: • C,HO or • C,H,O,N or • C,H,O,N,P