2. PowerPoint ® Lecture Slide Presentation by Patty Bostwick-Taylor, Florence-Darlington Technical College Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings PART A 2 Basic Chemistry

3. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Matter and Energy  Matter—anything that occupies space and has mass (weight)  Energy—the ability to do work  Chemical  Electrical  Mechanical  Radiant

4. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Composition of Matter  Elements—fundamental units of matter  96% of the body is made from four elements  Carbon (C)  Oxygen (O)  Hydrogen (H)  Nitrogen (N)  Atoms—building blocks of elements

5. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Atomic Structure  Nucleus  Protons (p + )  Neutrons (n 0 )  Outside of nucleus  Electrons (e - ) Figure 2.1

6. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Atomic Structure of Smallest Atoms Figure 2.2

7. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Identifying Elements  Atomic number—equal to the number of protons that the atom contains  Atomic mass number—sum of the protons and neutrons

8. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Isotopes and Atomic Weight  Isotopes  Have the same number of protons  Vary in number of neutrons Figure 2.3

9. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Isotopes and Atomic Weight  Atomic weight  Close to mass number of most abundant isotope  Atomic weight reflects natural isotope variation

10. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Radioactivity  Radioisotope  Heavy isotope  Tends to be unstable  Decomposes to more stable isotope  Radioactivity—process of spontaneous atomic decay

11. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Molecules and Compounds  Molecule—two or more like atoms combined chemically  Compound—two or more different atoms combined chemically Figure 2.4

12. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings – – – Chemical reactivity  Atoms tend to  complete a partially filled valence shell or  empty a partially filled valence shell This tendency drives chemical reactions… and creates bonds

13. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings – – H 2 (hydrogen gas) Covalent bond Bonds in Biology  Weak bonds  hydrogen bonds  attraction between + and –  hydrophobic & hydrophilic interactions  interactions with H 2 O  van derWaals forces  ionic  Strong bonds  covalent bonds  sharing electrons Hydrogen bond H2OH2O H2OH2O

14. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Nonpolar covalent bond  Pair of electrons shared equally by 2 atoms  example: hydrocarbons = C x H x  methane (CH 4 ) Lots of energy stored… & released balanced, stable, good building block

15. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings H H Oxygen Polar covalent bonds + + – – – –  Pair of electrons shared unequally by 2 atoms  example: water = H 2 O  oxygen has stronger “attraction” for the electrons than hydrogen  oxygen has higher electronegativity  water isa polar molecule  + vs – poles  leads to many interesting properties of water…

16. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Hydrogen bonding H O H H bonds  Polar water creates molecular attractions  attraction between positive H in one H 2 O molecule to negative O in another H 2 O  also can occur wherever an -OH exists in a larger molecule  Weak bond  but common in biology

17. AP Biology 2010-2011 Chemistry of Life Properties of Water

18. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings More about Water Why are we studying water? All life occurs in water  inside & outside the cell All life occurs in water  inside & outside the cell

19. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Chemistry of water  H 2 O molecules form H-bonds with each other  +H attracted to –O  creates a sticky molecule

20. Elixir of Life  Special properties of water 1.cohesion & adhesion  surface tension, capillary action 2.good solvent  many molecules dissolve in H 2 O  hydrophilic vs. hydrophobic 3.lower density as a solid  ice floats! 4.high specific heat  water stores heat 5.high heat of vaporization  heats & cools slowly Ice! I could use more ice!

21. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Try that with flour… or sugar…  Cohesion  H bonding between H 2 O molecules  water is “sticky”  surface tension  drinking straw  Adhesion  H bonding between H 2 O & other substances  capillary action  meniscus  water climbs up paper towel or cloth 1. Cohesion & Adhesion

22. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings How does H 2 O get to top of trees? Transpiration is built on cohesion & adhesion

23. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings What dissolves in water?  Hydrophilic  substances have attraction to H 2 O  polar or non-polar?

24. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings What doesn’t dissolve in water? fat (triglycerol) Oh, look hydrocarbons!  Hydrophobic  substances that don’t have an attraction to H 2 O  polar or non-polar?

25. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings And this has made all the difference! Ice! I could use more ice! 3. The special case of ice  Most (all?) substances are more dense when they are solid, but not water…  Ice floats!  H bonds form a crystal

26. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Why is “ice floats” important?  Oceans & lakes don’t freeze solid  surface ice insulates water below  allowing life to survive the winter  if ice sank…  ponds, lakes & even oceans would freeze solid  in summer, only upper few inches would thaw  seasonal turnover of lakes  sinking cold H 2 O cycles nutrients in autumn

27. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Specific heat & climate 4. Specific heat  H 2 O resists changes in temperature  high specific heat  takes a lot to heat it up  takes a lot to cool it down  H 2 O moderates temperatures on Earth

28. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings 5. Heat of vaporization Evaporative cooling Organisms rely on heat of vaporization to remove body heat

29. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Polarity  Covalently bonded molecules  Some are non-polar  Electrically neutral as a molecule  Some are polar  Have a positive and negative side Figure 2.8

30. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Chemical Bonds  Hydrogen bonds  Weak chemical bonds  Hydrogen is attracted to the negative portion of polar molecule  Provides attraction between molecules

31. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Patterns of Chemical Reactions  Synthesis reaction (A + B  AB)  Atoms or molecules combine  Energy is absorbed for bond formation  Decomposition reaction (AB  A + B)  Molecule is broken down  Chemical energy is released

32. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Synthesis and Decomposition Reactions Figure 2.10a

33. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Synthesis and Decomposition Reactions Figure 2.10b

34. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Patterns of Chemical Reactions  Exchange reaction (AB + C  AC + B)  Involves both synthesis and decomposition reactions  Switch is made between molecule parts and different molecules are made

35. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Patterns of Chemical Reactions Figure 2.10c Basic Chemistry

36. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Biochemistry: Essentials for Life  Organic compounds  Contain carbon  Most are covalently bonded  Example: C 6 H 12 O 6 (glucose)  Inorganic compounds  Lack carbon  Tend to be simpler compounds  Example: H 2 O (water)

37. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Important Inorganic Compounds  Salts  Easily dissociate into ions in the presence of water  Vital to many body functions  Include electrolytes which conduct electrical currents

38. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Dissociation of a Salt in Water Figure 2.11

39. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Important Inorganic Compounds  Acids  Release hydrogen ions (H + )  Are proton donors  Bases  Release hydroxyl ions (OH – )  Are proton acceptors  Neutralization reaction  Acids and bases react to form water and a salt

40. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.12 pH  Measures relative concentration of hydrogen ions  pH 7 = neutral  pH below 7 = acidic  pH above 7 = basic  Buffers—chemicals that can regulate pH change

41. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Important Organic Compounds  Carbohydrates  Contain carbon, hydrogen, and oxygen  Include sugars and starches  Classified according to size  Monosaccharides—simple sugars  Disaccharides—two simple sugars joined by dehydration synthesis  Polysaccharides—long-branching chains of linked simple sugars

42. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates Figure 2.13a–b

43. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates Figure 2.13c

44. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates Figure 2.14

45. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Lipids  Lipids are composed of C, H, O  long hydrocarbon chains (H-C)  “Family groups”  fats  phospholipids  steroids  Do not form polymers  big molecules made of smaller subunits  not a continuing chain

46. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Lipids  Common lipids in the human body  Neutral fats (triglycerides)  Found in fat deposits  Composed of fatty acids and glycerol  Source of stored energy

47. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Lipids  Common lipids in the human body (continued)  Phospholipids  Form cell membranes  Steroids  Include cholesterol, bile salts, vitamin D, and some hormones

48. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Lipids Figure 2.15b

49. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.15c Lipids  Cholesterol  The basis for all steroids made in the body

50. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Viva la difference!  Basic structure of male & female hormones is identical  identical carbon skeleton  attachment of different functional groups  interact with different targets in the body  different effects

51. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Important Organic Compounds  Proteins  Made of amino acids  Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur Figure 2.16

52. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Proteins  Account for over half of the body’s organic matter  Provide for construction materials for body tissues  Play a vital role in cell function  Act as enzymes, hormones, and antibodies

53. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Building proteins  Polypeptide chains have direction  N-terminus = NH 2 end  C-terminus = COOH end  repeated sequence (N-C-C) is the polypeptide backbone  can only grow in one direction

54. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.17a Proteins  Fibrous proteins  Also known as structural proteins  Appear in body structures  Examples include collagen and keratin  Stable

55. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.17b Proteins  Globular proteins  Also known as functional proteins  Function as antibodies or enzymes  Can be denatured

56. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.18a Enzymes  Act as biological catalysts  Increase the rate of chemical reactions

57. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Enzymes Figure 2.18b

58. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Important Organic Compounds  Nucleic Acids  Provide blueprint of life  Nucleotide bases  A = Adenine  G = Guanine  C = Cytosine  T = Thymine  U = Uracil  Make DNA and RNA Figure 2.19a

59. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Nucleic Acids  Deoxyribonucleic acid (DNA)  Organized by complimentary bases to form double helix  Replicates before cell division  Provides instructions for every protein in the body Figure 2.19c

60. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Important Organic Compounds  Adenosine triphosphate (ATP)  Chemical energy used by all cells  Energy is released by breaking high energy phosphate bond  ATP is replenished by oxidation of food fuels

61. Copyright © 2009 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.21 + ADP Solute Contracted muscle cell Product made Relaxed muscle cell Reactants Transport work Mechanical work Chemical work Membrane protein Solute transported Energy liberated during oxidation of food fuels used to regenerate ATP ATP P P P X Y (a) (b) (c) YX P P +