The Structure and Function of Macromolecules

1. The Structure and Function of Macromolecules Chapter 5 Biology – Campbell • Reece

2. Polymers • What is a polymer? • What is a monomer? • What are the 4 major biological macromolecules? • Which one is not (technically) a polymer?

3. Polymers in Nature

4. Condensation Reaction • Specifically a dehydration reaction (synthesis) • What happens? • Requires energy • Requires enzymes

5. Condensation Reaction

6. Hydrolysis • Reverse of dehydration reaction • What happens?

7. Hydrolysis

8. Carbohydrates • What elements make up carbs? • What are the monomers of carbs? • What are the functions of carbs?

9. Monosaccharides • CH2O • Major nutrients for cells • How are they made? • How is energy released from them?

10. Monosaccharides • Their carbon skeletons are raw materials for other organic molecules • Carbon skeleton varies from 3 to 7 carbons • Can be incorporated as monomers into disaccharides and polysaccharides

11. Monosacharides

12. Dissaccharides • What is a dissacharide? • Glycosidiclinkage • Examples: • Maltose (glucose + glucose) • Lactose (glucose + galactose) • Sucrose (glucose + fructose)

13. Dissacharides

14. Polysaccharides • Polymers of a few hundred or thousand monosaccharides • Important biological functions: • Energy storage (starch and glycogen) • Starch • Glycogen • Structural support (cellulose and chitin) • Cellulose • Chitin

15. Storage Polysaccharides

16. Lipids • Generally not big enough to be considered macromolecules • Hydrophobic or hydrophilic? • Mostly made of which two elements? • Examples?

17. Fats • What are the functions of fats? • Triacylglycerol or triglyceride • Made of glycerol and 3 fatty acids • glycerol • fatty acid • saturated • unsaturated

18. Fat Molecules

19. Phospholipids • What cellular structure is made up of phospholipids? • Only two fatty acids rather than three • Hydrocarbon tail • Phosphate head • Micelle

20. Phospholipids

21. Phospholipids • When placed in water, they self-assemble into a bilayer • Phospholipid Bilayer

22. Phospholipid bilayer

23. Steroids • What are steroids? • Cholesterol • Sex hormones

24. Proteins • Account for more than 50% of the dry mass of most cells • Functions?

26. Proteins • What are the monomers of proteins? • Polypeptides • What are the 5 parts of an amino acid?

27. Amino Acids

28. Hydrophobic Amino Acids

29. Hydrophilic Amino Acids

30. Proteins • What type of bond is formed between two amino acids? • What makes each polypeptide/ protein unique?

31. Protein Structure • Globular proteins • Fibrous proteins • A protein’s structure determines its function

32. Primary Structure • What is the primary structure? • Why is the sequence of amino acids important?

33. Protein Primary Structure

34. Secondary Structure • Alpha (α) helix • Beta (β) pleated sheet

35. Secondary Structure

36. Tertiary Structure • Hydrophobic interaction • Disulfide bridges

37. Hydrophobic vs. Hydrophilic • Which of these 3 shapes is the amino acid polymer most likely to adopt in water?

38. Tertiary Structure

39. Quaternary Structure Some proteins consist of two or more polypeptides

40. Denaturation of Proteins • What is denaturation? • Occurs when:

41. Denaturation of Proteins

42. Predicting Protein Folding • Why is predicting protein folding difficult? • Chaperonins • How would knowledge of protein folding be beneficial?

43. Nucleic Acids • DNA • What is it? • How is it copied? • How is it passed on? • Where is it found in a eukaryotic cell? • What is it used to make?

44. Nucleic Acids • RNA • What is it? • How is it involved in protein synthesis?

45. Nucleic Acids • What are the monomers of nucleic acids? • What are the 3 structures of a nucleotide? • What are the 2 types of nitrogenous bases? • How do the bases pair in DNA and RNA?

46. Nucleotides

47. DNA - The Double Helix • Who proposed the idea of the double helix structure of DNA?

48. DNA