BIOL 108 - Chp 2: Chemistry

1,257 views
1,201 views

Published on

Published in: Education
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
1,257
On SlideShare
0
From Embeds
0
Number of Embeds
4
Actions
Shares
0
Downloads
46
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

BIOL 108 - Chp 2: Chemistry

  1. 1. Chapter 2ChemistryBIOL 108 Rob Swatski Assoc Prof BiologyIntro to Bio Sci HACC-York 1
  2. 2. Learning GoalsDescribe what Understand Describe the Describe the Describe the Describe the atoms are, water’s structure & structure & structure & structure &their structure, features that function of function of function of function of & how they help it support carbohydrates. lipids. proteins. nucleic acids. bond. all life. 2
  3. 3. 3
  4. 4. 2.1–2.3Atoms formmolecules throughbonding. 4
  5. 5. 2.1 Everything is made of atoms. An element is a substance that cannot be broken down chemically into any other substances. An atom is a bit of matter that cannot be subdivided any further without losing its essential properties. 5
  6. 6. 6
  7. 7. Insert new figure 2.3 7
  8. 8. Radioactive Atoms A few atomic nuclei are not stable and break down spontaneously. These atoms are radioactive. They release, at a constant rate, a tiny, high- speed particle carrying a lot of energy. 8
  9. 9. insert new fig 2.4 9
  10. 10. 10
  11. 11. Take-Home Message 2.1 Everything around us, living or not, is made Atoms all have the same from atoms, the general structure.smallest unit into whichmaterial can be divided. They are made up of protons and neutrons in the nucleus and electrons, which circle far around the nucleus. 11
  12. 12. 2.2 An atom’selectronsdetermine how(and whether)the atom willbond with otheratoms. 12
  13. 13. Insert new fig 2-6 13
  14. 14. Insert fig 2-7 14
  15. 15. Insert new fig 2-8 15
  16. 16. Take-Home Message 2.2 The chemical characteristics of an atom depend upon number of electrons in their outermost shells. Atoms are most stable and least likely to bond with other atoms when their outermost electron shell is full. 16
  17. 17. 2.3 Atoms can bondtogether to formmolecules orcompounds. 17
  18. 18. 18
  19. 19. 19
  20. 20. Molecules = Products of Bonding 20
  21. 21. 21
  22. 22. 22
  23. 23. Insert fig 2-11 23
  24. 24. Insert fig 2-12 24
  25. 25. Take-Home Message 2.3 Atoms can be bound Covalent bonds, in which together in three different atoms share electrons, are ways. the strongest. In ionic bonds, the next Hydrogen bonds, thestrongest, one atom transfers weakest, involve the its electrons to another and attraction between a the two oppositely charged hydrogen atom and another ions are attracted to each polar atom or molecule. other, forming a compound. 25
  26. 26. 26
  27. 27. 2.4 Hydrogen bonds make water cohesive. 27
  28. 28. 28
  29. 29. Take-Home Message 2.4Water molecules easilyform hydrogen bonds, giving water great cohesiveness. 29
  30. 30. 2.5 Water has unusualproperties that make it critical to life. Cohesion Large heat capacity Low density as a solid Good solvent 30
  31. 31. Cohesion31 How?
  32. 32. 32
  33. 33. 33
  34. 34. 34
  35. 35. 35
  36. 36. Take-Home Message 2.5 The hydrogen bonds between water molecules give water several of its most important characteristics: cohesiveness,low density as a solid, the abilityto resist temperature changes, & broad effectiveness as a solvent 36
  37. 37. 2.6 Living systems are highly sensitiveto acidic and basic conditions. 37
  38. 38. Hydrogen Ions & Hydroxide IonsOH - H2O O O H H H Ionized Hydroxide Non-Ionized Water Molecule Molecule 38
  39. 39. AcidicpH Scale [H+] > [OH–] 0The amount of H+ in a solution is a measure of its Neutralacidity & is called pH. [H+] = [OH–] 7 Acids Basic Bases [H+] < [OH–] 14 39
  40. 40. 40
  41. 41. H+ Ions & Acids H+ very reactive Acids can donate H+ to other chemicals 41
  42. 42. Bases Low H+ & high OH-Antacids, baking soda, milk of magnesia 42
  43. 43. Buffers Can quickly absorbexcess H+ ions to keep a solution from becoming too acidic Can also quickly release H+ ions to counteract any increases in OH- concentration 43
  44. 44. Take-Home Message 2.6 The pH of a fluid is a measure of how acidic or basic a solution is and depends on the concentration of dissolved H+ ions present. Acids, such as vinegar, can donate protons to other chemicals while bases, including baking soda, bind with free protons. 44
  45. 45. 45
  46. 46. 2.7 Carbohydrates are macromolecules thatfunction as fuel. 46
  47. 47. Four Types of MacromoleculesCarbohydrates Lipids Proteins Nucleic Acids 47
  48. 48. Carbohydrates C, H, and O Primary fuel for organisms Cell structure 48
  49. 49. Take-Home Message 2.7 Carbohydrates are the Carbohydrates containprimary fuel for running all carbon, hydrogen, andcellular machinery and also oxygen, and generally haveform much of the structure the same number of carbon of cells in all life forms. atoms as they do H2O units. The C-H bonds of carbohydrates store a great deal of energy and are easily broken by organisms. 49
  50. 50. 2.8 Simple sugars are the most effective source of energy. Monosaccharides 3-7 carbon atoms Glucose & fructose 50
  51. 51. GlucoseMost carbohydrates are ultimately converted into glucose Glucose provides energy for the body’s cells Stored temporarily as glycogen 51
  52. 52. What is “carbo-loading”? 52
  53. 53. 53
  54. 54. Take-Home Message 2.8The simplest carbohydratesare called monosaccharides The sugar glucose is the most or simple sugars. They important carbohydrate to contain from 3-7 carbon living organisms. atoms. Glucose in the bloodstream can be used as an energy source, can be stored as glycogen in the muscles and liver for later use, or can be converted to fat. 54
  55. 55. 2.9 Complex carbohydrates aretime-released packets of energy. More than 1 sugar unit: monosaccharide Disaccharides: sucrose, lactose Polysaccharides: starch, cellulose 55
  56. 56. Starch100’s of glucose moleculesjoined together Barley, wheat,rye, corn, & rice Glycogen:“animal starch” 56
  57. 57. 57
  58. 58. Take-Home Message 2. 9 Multiple simple carbohydrates sometimes link together into more complex carbohydrates. Types of complex carbohydrates include starch, the primary form of energy storage in plants, and glycogen, a primary form of energy storage in animals. 58
  59. 59. 2.10 Not allcarbohydratesare digestible. Cellulose Chitin 59
  60. 60. 60
  61. 61. Fiber“Roughage”Colon cancerprevention & reduction Termites ecological role 61
  62. 62. Take-Home Message 2.10 Some complex carbohydrates, including chitin and cellulose, cannot be digested by most animals. Such indigestible carbohydrates in the diet, called fiber, aid in digestion and have numerous health benefits. 62
  63. 63. 2.11–2.13Lipids storeenergy for a rainyday. 63
  64. 64. 2.11 Lipids are macromolecules with several functions, including energy storage. 64
  65. 65. Why does a saladdressing made with vinegar and oil separate into twolayers shortly after you shake it? Hydrophilic Hydrophobic 65
  66. 66. Take-Home Message 2.11 Lipids are non-soluble in water and greasy to the touch. They are valuable to organisms in long-term energy storage and insulation, membrane formation, and as hormones. 66
  67. 67. 2.12 Fats are tasty molecules tooplentiful in our diets. Glycerol: “head” region Fatty acid “tails” Triglycerides 67
  68. 68. 68
  69. 69. 69
  70. 70. Saturated &Unsaturated Fats # of bonds in the hydrocarbon chain in a fatty acid Health considerations 70
  71. 71. 71
  72. 72. 72
  73. 73. 73
  74. 74. Carotid arteryplaque 74
  75. 75. Take-Home Message 2.12 Characterized by long Fats, including the triglycerides hydrocarbon tails, fats effectivelycommon in the food we eat, are store energy in the bonds one type of lipid. connecting the molecules. Their caloric density is responsible for humans’ preferring fats to other macromolecules in the diet, and is also responsible for their association with obesity and illness in the modern world. 75
  76. 76. 2.13 Cholesteroland phospholipids are used to buildsex hormones and membranes. Not all lipids are fats Sterols 76
  77. 77. 77
  78. 78. Cholesterol Important component of most cell membranes. Can attach to blood vessel walls and cause them to thicken. Cells in our liver produce almost 90% of the circulating cholesterol. 78
  79. 79. SteroidHormones Estrogen Testosterone 79
  80. 80. Phospholipids & Waxes Phospholipids are the major component of the cell membrane. Waxes are strongly hydrophobic. 80
  81. 81. 81
  82. 82. Take-Home Message 2.13 Cholesterol and Both are importantphospholipids are lipids components in cell that are not fats. membranes. Cholesterol also serves as a precursor to steroid hormones, important regulators of growth and development. 82
  83. 83. 2.14–2.18Proteins areversatilemacromoleculesthat serve asbuilding blocks. 83
  84. 84. 2.14 Proteinsare versatilemacromoleculesthat serve asbuilding blocks. 84
  85. 85. Keratin:structural protein 85
  86. 86. AminoAcids20 differentamino acids Strungtogether to make proteins 86
  87. 87. 87
  88. 88. Nonpolar Amino Acids Glycine Alanine Valine Leucine Isoleucine (Gly or G) (Ala or A) (Val or V) (Leu or L) (Ile or I)Methionine Phenylalanine Tryptophan Proline(Met or M) (Phe or F) (Trp or W) (Pro or P) 88
  89. 89. Take-Home Message 2.14 Unique combinations of 20 amino acids give rise to proteins, the chief building blocks of physical structures that make up all organisms. Proteins perform myriad functions, from assisting chemical reactions to causing blood clotting to building bones to fighting microorganisms. 89
  90. 90. 2.15 Proteins are an essential dietary component. Growth Repair Replacement 90
  91. 91. Complete Proteins Have all essential amino acids Incomplete proteins Complementary proteins 91
  92. 92. Insert new fig 2-38 92
  93. 93. Take-Home Message 2.15 Of these amino acids, aboutTwenty amino acids make half are essential for up all the proteins humans: they cannot be necessary for growth, synthesized by the body sorepair, and replacement of must be consumed in the tissue in living organisms. diet. Complete proteins contain all essential amino acids, while incomplete proteins do not. 93
  94. 94. 2.16 Protein functions are influenced by their three-dimensional shape. 94
  95. 95. 95
  96. 96. 96
  97. 97. Silk =  pleated sheet 97
  98. 98. too freakin’ cute… …it has eyelashes for crying out loud! 98
  99. 99. 99
  100. 100. 100
  101. 101. 101
  102. 102. Why do some people have curly hair and others have straight hair? 102
  103. 103. Take-Home Message 2.16The particular amino This shape determines acid sequence of a many of the proteins protein determines features, such as which how it folds into a molecules it will particular shape. interact with. When a proteins shape is deformed, the protein usually loses its ability to function. 103
  104. 104. 2.17 Enzymesare proteinsthat initiateand speed upchemicalreactions. 104
  105. 105. Enzymatic proteins =Substrates CatalystsActiveSite Enzyme 105
  106. 106. 106
  107. 107. 107
  108. 108. Activation Energy Chemical reactions occurring in organisms can either release energy or consume energy. Ineither case, the reaction needs a little “push” in order to initiate the reaction―called activation energy. Enzymes act as catalyst by lowering the activation energy. 108
  109. 109. Take-Home Message 2.17 Enzymes are proteins that help initiate and speed up chemical reactions. They arent permanently altered in the process but rather can be used again and again. 109
  110. 110. 2-18 Enzymes regulate reactions in several ways(but malformed enzymes can cause problems). 110
  111. 111. 111
  112. 112. 112
  113. 113. 113
  114. 114. 114
  115. 115. “Misspelled” Proteins Incorrect amino acid sequence Active site disruptions Phenylketonuria 115
  116. 116. 116
  117. 117. 117
  118. 118. Take-Home Message 2.18 Enzyme activity is influenced by physical factors such as temperature and pH, as well as chemical factors, including enzyme and substrate concentrations. Inhibitors and activators are chemicals that bind to enzymes, and by blocking the active site or altering the shape or structure of the enzyme can change the rate at which the enzyme catalyzes reactions. 118
  119. 119. 2.19–2.21Nucleic acidsstore informationon how to buildand run a body. 119
  120. 120. 2.19 Nucleicacids aremacromoleculesthat storeinformation. 120
  121. 121. Two Types ofNucleic Acids Ribonucleic acid (RNA) Deoxyribonucleic acid (DNA) Both play central roles in directing the production of proteins. 121
  122. 122. 122
  123. 123. Information Storage The information in a molecule of DNA is determined by its sequence of bases. Adenine, Guanine, Cytosine, & Thymine CGATTACCCGAT 123
  124. 124. Take-Home Message 2.19 The nucleic acids DNA and RNA are macromolecules that store information by having unique sequences of molecules. Both play central roles in directing protein production in organisms. 124
  125. 125. 2.20 DNAholds thegeneticinformationto build anorganism.125
  126. 126. Base-Pairing A&T C&G What is the complimentary strand to this strand: CCCCTTAGGAACC? 126
  127. 127. Take-Home Message 2.20 DNA is like a ladder in which the long vertical element of the ladder is made from a sequence of sugar-phosphate-sugar- phosphate molecules and rungs are nucleotide bases. The sequence of nucleotide bases contains the information about how to produce a particular protein. 127
  128. 128. 2.21 RNA is a universal translator, reading DNA and directing protein production. 128
  129. 129. 129
  130. 130. RNA differs from DNA in threeimportant ways. The sugar molecule of the sugar-phosphate backbone Single-stranded Uracil (U) replaces thymine (T) 130
  131. 131. Take-Home Message 2.21 RNA acts as a middlemanmolecule—taking the instructionsfor protein production from DNAto another part of the cell where, in accordance with the RNA instructions, amino acids are pieced together into proteins. 131

×