Chapter 3 Macromolecules of Life

1. Chapter 3Macromolecules of Life Kristi Schramm

2. I. Macromolecules: • Organic molecules contain • Carbon and Hydrogen • Elements that make up almost all of the weight of living things: CHNOPS • Carbon • Hydrogen • Nitrogen • Oxygen • Phosphorous • Sulfur

3. A. Carbon: A molecule with many possibilities 1. Forms Chains • Ex: Octane • CH3(CH2)6CH3 2. Forms Rings • Ex: Cyclohexane • C6H12

4. 3. Functional Groups Added to a Carbon Skeleton: In place of a hydrogen on a carbon chain/ring you can have a functional group. A functional group changes the carbon chain/ring into a certain type of compound.

5. Example of Carbon Chain with Functional Group: • Ethane: • C2H6 • No functional groups. • Hydrophobic: Non-Polar • Ethanol: • C2H5OH • Addition of a hydroxyl group makes it an alcohol • It is now Hydrophilic: Polar

6. II. Four Macromolecules of Life: • Proteins • Carbohydrates • Lipids • Nucleic Acids

7. A. Macromolecules Overview:

8. B. Macromolecules are Polymers • Polymer: A large ‘biomolecule’ (organic macromolecule) made up of smaller subunits called monomers. • During life processes polymers are built up and broken down.

9. C. Macromolecules:Synthesis & Degradation • Dehydration Reaction: a hydrogen and hydroxyl group are removed forming water • Hydrolysis: Breaks a water molecule, adds hydroxyl and H+ to the broken down monomers. Building up (synthesizing) Breaking down (degradation)

10. Proteins: Structures and Functions in Living things

11. I. Protein Functions: (6) 1) Metabolism: Enzymes that catalyze all of life’s reactions. • Example: Salivary Amylase found in mouth, breaks down carbohydrates.

12. Protein Functions: 2) Support: Ligaments, tendons and skin: all made of collagen, tough and flexible protein

13. Protein Functions: 3) Motion: Actin and Myosin are two proteins that make up muscles

14. Protein Functions: 4) Transport: Transport proteins allow molecules to move in and out of cells. Other proteins help move molecules throughout the body (ex: Hemoglobin)

15. Protein Functions: 5) Defense: The immune system response sends antibodies to capture foreign substances (antigens) in the body. Antibodies are proteins.

16. Protein Functions: 6) Regulation: Hormones-these proteins send messages that influence cell metabolism. Ex: Insulin: regulates blood sugar levels

17. II. Monomers of Proteins: • Amino acids are the monomer of proteins • 20 different amino acids: • All have a common amino group, but differ in based on which ‘R group’ they have. • Some are polar, some are nonpolar

18. Amino Acids: • Attached to one another by peptide bonds. • The O- and H+ do not share electrons evenly and create an uneven charge (polar).

19. III. Structure IS Function: • A protein’s exact shape determines it’s purpose (function). • Any change in the shape will prevent the protein from doing it’s job. • There are 4 levels of structure in proteins: • Primary • Secondary • Tertiary • Quaternary

20. Protein Structure: 1) Primary Structure: • sequence of amino acids: the number order and type of amino acids determines a proteins primary structure.

21. Protein Structure: 2) Secondary Structure: H-Bonds form between Amino Acids. • α helix • Every 4th amino acid forms H-bonds that cause helix • β pleated sheets • Polypeptide chain folds back and forth on itself. • Hydrogen bonds form between amino acids.

22. Protein Structure: 3) Tertiary Structure: Hydrogen, Covalent and Ionic bonds can form between ‘R-groups’ of amino acids. • Causes protein to fold over itself into a glob: hence the name ‘globular proteins’ (give to proteins with Tertiary Structure:

23. Protein Structure: 4) Quaternary Structure: When more than one polypeptide chain bond together. • Each protein has it’s own primary, secondary and tertiary structure.

24. Protein Folding Diseases • Chaperone Proteins: • Proteins that assist newly formed proteins in the folding of their secondary, tertiary and/or quaternary structures. • Correct any misfolded proteins • Alzheimer's Disease and Cystic fibrosis caused by lack of Chaperone Proteins.

25. Protein Folding Disease • Prions: • Misfolded proteins that cause other proteins with the same primary structure to misfold in an identical way. • Ex: Mad Cow disease

26. Nucleic Acids: Stores Genetic Information in Living Things

27. I. Types of Nucleic Acids • DNA: Deoxyribonucleic Acid • RNA: Ribonucleic Acid • Co-enzymes: nonprotein organic molecules that assist in enzyme reactions • ATP: Adenosine Triphosphate

28. II. Monomer: Nucleotides A. Nucleic acids are made up of nucleotides • Three parts: • Pentose Sugar (5 sided) (ex: ribose) • Phosphate group (phosphoric acid) • Nitrogen base (A, T, G, C, U)

29. Purines: Ex: Guanine, Adenine Drawing: Pyrimidines: Ex: Cytosine Thymine (Uracil) Drawing: B. Two types of Nitrogen Bases:

30. C. DNA Bonding: Bases: • Adenine = Thymine • Always form 2 bonds • Guanine = Cytosine • Always form 3 H bonds DNA Backbone: • Sugar and Phosphate groups are held together by covalent bonds

31. ATP: Adenosine TriPhosphate • Adenine and ribose = Adenosine • Three phosphates • The bond between the last two phosphates is unstable and easily broken (forms ADP and P) • The breaking of this bond releases energy that cells use for many cell processes.

32. Carbohydrates: Energy for all Life on Earth

33. 1) Monosaccharides • Ready to go Energy • Have many hydroxyl groups (OH) that make it very soluble. • Example: Glucose and Isomers of glucose (fructose and galactose) • Used to make ATP Glucose Galactose

34. 2) Disaccharides: • Two monosaccharides bonded together by a dehydration reaction. • Examples: • Maltose = Glucose + Glucose • Sucrose (table sugar)= Glucose + Fructose • Lactose (in dairy) = Glucose + Galactose

35. 3) Polysaccharides: • Short term energy storage • Very large molecules, hard to dissolve, cannot fit through a cell membrane A. Example: Glycogen Glucose

36. A. Glycogen: • Animals store glucose in large glycogen molecules in the liver. • Insulin controls storage of glucose as glycogen.

37. Polysaccharides as a Structure

38. Polysaccharides as a Structure Cellulose Chitin Peptidoglycan

39. Lipids: Long Term energy Storage Non-Polar Hydrocarbon chains. Will not dissolve in water

40. I. Lipids and Functions • Fats: Insulation/blubber in animals • Oils: Energy storage for Plants • Phospholipids: Make up cellular membrane • Steroids: Plasma membrane and sex hormones • Waxes: prevent water loss in plants. Ear wax and bees wax.

41. II. Oils and Fats: • All H-Bonds • No double bonds • Packed tightly together • Solid at room Temp • Cause arterial damage and blockages • Found in animals • Contain less H in the C-chain • Contains C=C (double bonds) • ‘kinks’ prevent tight packing • Liquid at room temp • Healthier to eat and cook with. • Found in plants Oils Fats A. Saturated B. Unsaturated

42. Unsaturated vsSatruated

43. III. Phospholipids: • In place of a 3rd fatty acid: polar phosphate group • Unsaturated fatty acids cause kinks in the lipid. • Prevents tight packing of cells: makes cell membranes ‘fluid’ (AKA: fluid mosaic model).

44. IV. Steroids: • Made of 4 fused C-Rings • Cholesterol: • Provides structure to cell membrane • Estrogen and Testosterone: Steroid hormones that influence development Hormones: chemical released in body to send message to another part of the body.

45. A. Two types of hormones • Steroid Hormones: • Contain lipids Control sexual maturity, fertility, aging Ex: Extrogen and Testtosterone • Peptide Hormones • Contain proteins not lipids Sleep and sugar concentration Ex: Growth Hormone, Insulin, adrenaline

46. V. Wax: • Long chain of fatty acids with long chains of alcohol attached • Solid at room temp • Coats the outside of plants to prevent water loss • Earwax: contains substances that repel/harm insects • Beeswax: used to make hives.