1. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh Edition Solomon Berg Martin Chapter 3 The Chemistry of Life: Organic Compounds

2. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Organic compounds Carbon atoms covalently bonded form the backbone of the molecule Very simple carbon compounds are considered inorganic if carbon is not bonded to another carbon or hydrogen Carbon dioxide is an example of inorganic carbon

3. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Carbon forms four covalent bonds, producing many shapes

4. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Isomers: compounds with the same molecular formulas, but different structures Structural isomers Geometric isomers Enantiomers

5. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Isomers

6. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Functional groups Groups of atoms that determine the types of chemical reactions and associations Most readily form associations with with other molecules

7. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Functional groups Hydroxyl Carbonyl Carboxyl Amino Phosphate Sulfhydryl

8. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Polymers Most macromolecules are polymers Produced by linking monomers

9. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds A simple polymer

10. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Carbohydrates Sugars Starches Cellulose Carbohydrate means hydrate (water of) carbon Reflects 2:1 ratio of hydrogen to oxygen

11. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Monosaccharides Contain three to seven carbon items Glucose most abundant monosaccharide

12. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Monosaccharides, 2-D structures

13. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Disaccharide “Two sugars” Two monosaccharide rings joined by a glycosidic linkage

14. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Derivatives of monosaccharides are important biological molecules Carbohydrates may combine with proteins to form glycoproteins

15. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Lipids Heterogeneous group of compounds Consist mainly of carbon and hydrogen Some are important hormones and some are used for energy storage Soluble in nonpolar solvents, such as ether, and relatively insoluble in water Important groups include fats, phospholipids, carotenoids, etc.

16. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Triacylglycerols (fats) Most abundant lipids in living organisms When metabolized, yield twice as much energy as carbohydrates Carbohydrates and proteins can be transformed by enzymes into fats

17. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Triacylglycerol, the main storage lipid

18. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Saturated fatty acids contain maximum possible number of hydrogen atoms Unsaturated fatty acids include one or more adjacent pairs of carbon atoms joined by a double bond Monounsaturated fatty acids—one double bond Polyunsaturated fatty acids—more than one double bond

19. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Phospholipids Amphipathic lipids Two ends differ physically and chemically Uniquely suited to function as fundamental components of cell membranes

20. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds A phospholipid and a phospholipid bilayer

21. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Carotenoids Orange and yellow plant pigments Classified with lipids Play a role in photosynthesis Consist of isoprene units Animals convert to vitamin A

22. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Isoprene- derived compounds

23. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Steroid Carbon atoms in four attached rings Consist of isoprene units Cholesterol, bile salts, etc. Involved in regulating metabolism

24. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Proteins Macromolecules composed of amino acids Most versatile cell components Most enzymes are proteins Proteins largely determine what a cell looks like and how it functions

25. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds

26. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Four levels of organization Primary structure is the amino acid sequence Secondary structure results from hydrogen bonding Tertiary structure depends on interactions among side chains Quaternary structure results from interactions among polypeptides

27. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Primary structure of a polypeptide

28. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Secondary structure of a protein

29. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Tertiary structure of a protein

30. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Quaternary structure of a protein

31. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Nucleic acids Transmit hereditary information Determine what proteins a cell manufactures Two classes found in cells –Ribonucleic acid (RNA) –Deoxyribonucleic acid (DNA) Polymers of nucleotides

32. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Components of nucleotides Five-carbon sugar –Deoxyribose (DNA) –Ribose (RNA) One or more phosphate groups Nitrogenous base of either a double-ring purine or a single-ring pyrimidine

33. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Components of nucleotides

34. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds RNA, a nucleic acid

35. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 3 The Chemistry of Life: Organic Compounds Classes of biologically important organic compounds