2. Chemistry J. Cauthers Living Environment

4. Atoms Atoms are the building blocks of ALL matter. Cannot be subdivided any further, through chemical means.

5. Basic Definitions ELEMENT - Substance made from only one type of atom - E.g. Calcium Ca COMPOUNDS: made from two or more different atoms and joined chemically in definite proportions –E.g. Carbon Dioxide CO 2

6. Inside and Atom Nucleus –Protons (+) –Neutrons (0) Isotopes have different #s of neutrons and some are radioactive Orbitals –Electrons (-) Give atoms their unique properties

7. Organic vs. Inorganic Compounds All chemical compounds are broken into two categories: 1) Organic compounds 2) Inorganic Compounds

8. Organic Compounds Always contain: Carbonand Hydrogen

9. Organic Compounds cont. Other elements found in organic compounds include: Oxygen Nitrogen Phosphorus Sulfur

10. Organic Compounds Most common elements to appear in organic compounds are: CHNOPS!!!

11. Inorganic Compounds Any compound that isn’t organic Note: Some contain carbon!!! (CO 2 )

12. Agua!!! Why do we need to talk about water in a class about biology? Life would not exist were it not for water.

13. Water Equation for water is H 2 O Is water an organic, or inorganic compound? Inorganic (no carbon)

14. Brita Water is called a POLAR MOLECULE (a partial + and – charge) The positive end of one water molecule (H end) will be attracted to the negative end of another water molecule (O end).

15. PûrPûr -+ - + Hydrogen Oxygen

16. Polar Properties Cohesion: attraction between water molecules. Surface tension: h olds drops of water together especially at surface.

17. Perrier Surface tension in action:

18. Joe Water Surface tension again:

19. Heavy Water (deuterium)

20. ADHESION attraction of one substance to another Explains why water is such a good solvent…other substances (polar ones) are attracted to water. Polar Properties

21. Adhesion accounts for capillary action or capillarity. Capillary action Capillary action : water rises up any narrow space due to attraction with the substance it is interacting with (i.e. glass, or plant roots.)

22. Acids and Bases Water and other compounds can break apart and form ions in solution Acids give off H+ ions Bases give off OH- ions

23. pH Concentration of H+ ions More H+ ions the lower the pH Acids – pH 1<7 Bases – pH >7-14 Neutral = ~7

25. Organic Compounds Four Types –Carbohydrates –Proteins –Lipids –Nucleic Acids

26. Carbohydrates Building blocks: sugars Contain C, H and O in a ratio of 2H:1O Main source of energy Structural purposes Long chains form starches Plants store extra as starch –Think potatoes! Animals store extra as glycogen in liver

27. Starch

28. Carbohydrates Monosaccharides – single sugars –Glucose, fructose Disaccharides – two sugars –Maltose, Sucrose Polysaccharides – many sugars –Starch, cellulose

29. Maltose Sucrose

30. Proteins Building Blocks: amino acids Contain: C, H, O, N Control rate of reactions Regulate cell processes Form bones and muscles Transport substances in or out of cells Help to fight disease

31. Proteins Form 3D structures by folding Form enzymes- regulate reactions

32. Amino Acids

33. Lipids Building Blocks: Glycerol, 3Fatty acids Contain: C, H, and O Stored energy Part of cell membrane Steroids and chemical messengers E.g. - Fats, oils and waxes

34. Saturated – only single bonds between C and H Unsaturated – at least one double bond between C and H

35. Nucleic Acids Building blocks: Nucleotides –5 C sugar –nitrogenous base –Phosphorus Contain C, H, O, N and P Store and transmit genetic info

36. Nucleic Acids Two types –DNA - Deoxyribonucleic acid Sugar is deoxyribose Inside nucleus Double stranded –RNA – Ribonucleic acid Sugar is ribose Involved with protein synthesis Single stranded

37. Enzymes Biological catalysts that speed up chemical reactions Lower energy need to get reaction going (Activation energy) Made of proteins

39. Catalyzed Reactions

40. Enzymes again… The object enzymes work upon are called substrates. Specific to the object they work upon Most enzymes are named according to what they work upon. Naming: change the ending of the substrate name to –ase

41. Enzyme Naming Substrate Enzyme Maltose ?? Sucrose ?? Lipid ??