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1 | (39) |
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Unity and Diversity of Cells |
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1 | (4) |
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Cells Vary Enormously in Appearance and Function |
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2 | (1) |
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Living Cells All Have a Similar Basic Chemistry |
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3 | (1) |
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All Present-Day Cells Have Apparently Evolved from the Same Ancestor |
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4 | (1) |
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Genes Provide the Instructions for Cellular Form, Function, and Complex Behavior |
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5 | (1) |
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Cells Under the Microscope |
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5 | (6) |
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The Invention of the Light Microscope Led to the Discovery of Cells |
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6 | (1) |
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Cells, Organelles, and Even Molecules Can Be Seen Under the Microscope |
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7 | (4) |
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11 | (5) |
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Procaryotes Are the Most Diverse of Cells |
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14 | (1) |
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The World of Procaryotes Is Divided into Two Domains: Eubacteria and Archaea |
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15 | (1) |
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16 | (11) |
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The Nucleus Is the Information Store of the Cell |
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16 | (1) |
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Mitochondria Generate Energy from Food to Power the Cell |
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17 | (1) |
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Chloroplasts Capture Energy from Sunlight |
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18 | (1) |
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Internal Membranes Create Intracellular Compartments with Different Functions |
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19 | (3) |
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The Cytosol Is a Concentrated Aqueous Gel of Large and Small Molecules |
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22 | (1) |
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The Cytoskeleton Is Responsible for Directed Cell Movements |
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22 | (1) |
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The Cytoplasm Is Far from Static |
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23 | (1) |
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Eucaryotic Cells May Have Originated as Predators |
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24 | (3) |
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27 | (12) |
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Molecular Biologists Have Focused on E. coli |
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28 | (1) |
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Brewer's Yeast Is a Simple Eucaryotic Cell |
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28 | (1) |
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Arabidopsis Has Been Chosen Out of 300,000 Species as a Model Plant |
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28 | (1) |
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The World of Animals Is Represented by a Fly, a Worm, a Mouse, and Homo sapiens |
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29 | (4) |
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Comparing Genome Sequences Reveals Life's Common Heritage |
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33 | (6) |
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Chemical Components of Cells |
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39 | (44) |
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39 | (11) |
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Cells Are Made of Relatively Few Types of Atoms |
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40 | (1) |
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The Outermost Electrons Determine How Atoms Interact |
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41 | (2) |
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Ionic Bonds Form by the Gain and Loss of Electrons |
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43 | (2) |
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Covalent Bonds Form by the Sharing of Electrons |
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45 | (1) |
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Covalent Bonds Vary in Strength |
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46 | (1) |
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There Are Different Types of Covalent Bonds |
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47 | (1) |
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Water Is Held Together by Hydrogen Bonds |
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48 | (1) |
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Some Polar Molecules Form Acids and Bases in Water |
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49 | (1) |
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50 | (8) |
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A Cell Is Formed from Carbon Compounds |
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50 | (1) |
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Cells Contain Four Major Families of Small Organic Molecules |
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51 | (1) |
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Sugars Are Energy Sources for Cells and Subunits of Polysaccharides |
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52 | (1) |
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Fatty Acids Are Components of Cell Membranes |
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53 | (2) |
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Amino Acids Are the Subunits of Proteins |
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55 | (1) |
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Nucleotides Are the Subunits of DNA and RNA |
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56 | (2) |
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58 | (25) |
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Macromolecules Contain a Specific Sequence of Subunits |
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59 | (3) |
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Noncovalent Bonds Specify the Precise Shape of a Macromolecule |
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62 | (1) |
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Noncovalent Bonds Allow a Macromolecule to Bind Other Selected Molecules |
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63 | (20) |
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Energy, Catalysis, and Biosynthesis |
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83 | (36) |
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Catalysis and the Use of Energy by Cells |
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84 | (22) |
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Biological Order Is Made Possible by the Release of Heat Energy from Cells |
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85 | (3) |
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Photosynthetic Organisms Use Sunlight to Synthesize Organic Molecules |
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88 | (1) |
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Cells Obtain Energy by the Oxidation of Organic Molecules |
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89 | (1) |
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Oxidation and Reduction Involve Electron Transfers |
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90 | (1) |
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Enzymes Lower the Barriers That Block Chemical Reactions |
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91 | (2) |
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The Free-Energy Change for a Reaction Determines Whether It Can Occur |
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93 | (1) |
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The Concentration of Reactants Influences the Free-Energy Change and a Reaction's Direction |
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94 | (1) |
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The Equilibrium Constant Indicates the Strength of Molecular Interactions |
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95 | (3) |
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For Sequential Reactions, the Changes in Free Energy Are Additive |
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98 | (2) |
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Rapid Diffusion Allows Enzymes to Find Their Substrates |
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100 | (1) |
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Vmax and KM Measure Enzyme Performance |
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101 | (5) |
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Activated Carrier Molecules and Biosynthesis |
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106 | (13) |
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The Formation of an Activated Carrier Is Coupled to an Energetically Favorable Reaction |
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106 | (1) |
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ATP Is the Most Widely Used Activated Carrier Molecule |
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107 | (1) |
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Energy Stored in ATP Is Often Harnessed to Join Two Molecules Together |
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108 | (1) |
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NADH and NADPH Are Important Electron Carriers |
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109 | (2) |
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There Are Many Other Activated Carrier Molecules in Cells |
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111 | (1) |
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The Synthesis of Biological Polymers Requires an Energy Input |
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112 | (7) |
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Protein Structure and Function |
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119 | (50) |
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The Shape and Structure of Proteins |
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119 | (24) |
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The Shape of a Protein Is Specified by Its Amino Acid Sequence |
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121 | (3) |
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Proteins Fold into a Conformation of Lowest Energy |
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124 | (1) |
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Proteins Come in a Wide Variety of Complicated Shapes |
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125 | (1) |
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The α Helix and the β Sheet Are Common Folding Patterns |
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126 | (8) |
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Helices Form Readily in Biological Structures |
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134 | (1) |
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β Sheets Form Rigid Structures at the Core of Many Proteins |
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135 | (1) |
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Proteins Have Several Levels of Organization |
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136 | (1) |
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Few of the Many Possible Polypeptide Chains Will Be Useful |
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137 | (1) |
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Proteins Can Be Classified into Families |
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138 | (1) |
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Large Protein Molecules Often Contain More Than One Polypeptide Chain |
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139 | (1) |
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Proteins Can Assemble into Filaments, Sheets, or Spheres |
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140 | (1) |
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Some Types of Proteins Have Elongated Fibrous Shapes |
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141 | (1) |
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Extracellular Proteins Are Often Stabilized by Covalent Cross-Linkages |
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142 | (1) |
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143 | (7) |
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All Proteins Bind to Other Molecules |
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143 | (1) |
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The Binding Sites of Antibodies Are Especially Versatile |
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144 | (1) |
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Enzymes Are Powerful and Highly Specific Catalysts |
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145 | (1) |
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Lysozyme Illustrates How an Enzyme Works |
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146 | (3) |
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Tightly Bound Small Molecules Add Extra Functions to Proteins |
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149 | (1) |
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How Proteins Are Controlled |
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150 | (19) |
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The Catalytic Activities of Enzymes Are Often Regulated by Other Molecules |
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151 | (1) |
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Allosteric Enzymes Have Two Binding Sites That Influence One Another |
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|
151 | (2) |
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Phosphorylation Can Control Protein Activity by Triggering a Conformational Change |
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153 | (1) |
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GTP-Binding Proteins Are Also Regulated by the Cyclic Gain and Loss of a Phosphate Group |
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|
154 | (1) |
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Nucleotide Hydrolysis Allows Motor Proteins to Produce Large Movements in Cells |
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155 | (1) |
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Proteins Often Form Large Complexes That Function as Protein Machines |
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|
156 | (1) |
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Large-Scale Studies of Protein Structure and Function Are Increasing the Pace of Discovery |
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157 | (12) |
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169 | (26) |
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The Structure and Function of DNA |
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170 | (7) |
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A DNA Molecule Consists of Two Complementary Chains of Nucleotides |
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171 | (5) |
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The Structure of DNA Provides a Mechanism for Heredity |
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|
176 | (1) |
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The Structure of Eucaryotic Chromosomes |
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177 | (18) |
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Eucaryotic DNA Is Packaged into Chromosomes |
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|
178 | (1) |
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Chromosomes Contain Long Strings of Genes |
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179 | (2) |
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Chromosomes Exist in Different States Throughout the Life of a Cell |
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181 | (2) |
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Interphase Chromosomes Are Organized Within the Nucleus |
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|
183 | (1) |
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The DNA in Chromosomes Is Highly Condensed |
|
|
183 | (1) |
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Nucleosomes Are the Basic Units of Chromatin Structure |
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184 | (2) |
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Chromosomes Have Several Levels of DNA Packing |
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186 | (1) |
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Interphase Chromosomes Contain Both Condensed and More Extended Forms of Chromatin |
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|
187 | (2) |
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Changes in Nucleosome Structure Allow Access to DNA |
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|
189 | (6) |
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DNA Replication, Repair, and Recombination |
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|
195 | (34) |
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196 | (13) |
|
Base-Pairing Enables DNA Replication |
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|
196 | (1) |
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|
196 | (1) |
|
Base-Pairing Enables DNA Replication |
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|
196 | (1) |
|
DNA Synthesis Begins at Replication Origins |
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|
197 | (4) |
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New DNA Synthesis Occurs at Replication Forks |
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201 | (1) |
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The Replication Fork Is Asymmetrical |
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|
202 | (1) |
|
DNA Polymerase Is Self-correcting |
|
|
203 | (1) |
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Short Lengths of RNA Act as Primers for DNA Synthesis |
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|
204 | (2) |
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Proteins at a Replication Fork Cooperate to Form a Replication Machine |
|
|
206 | (1) |
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Telomerase Replicates the Ends of Eucaryotic Chromosomes |
|
|
207 | (1) |
|
DNA Replication Is Relatively Well Understood |
|
|
208 | (1) |
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|
209 | (6) |
|
Mutations Can Have Severe Consequences for an Organism |
|
|
209 | (1) |
|
A DNA Mismatch Repair System Removes Replication Errors That Escape the Replication Machine |
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|
210 | (2) |
|
DNA Is Continually Suffering Damage in Cells |
|
|
212 | (1) |
|
The Stability of Genes Depends on DNA Repair |
|
|
213 | (1) |
|
The High Fidelity of DNA Maintenance Allows Closely Related Species to Have Proteins with Very Similar Sequences |
|
|
214 | (1) |
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|
215 | (14) |
|
Homologous Recombination Results in an Exact Exchange of Genetic Information |
|
|
215 | (1) |
|
Recombination Can Also Occur Between Nonhomologous DNA Sequences |
|
|
216 | (1) |
|
Mobile Genetic Elements Encode the Components They Need for Movement |
|
|
217 | (1) |
|
A Large Fraction of the Human Genome Is Composed of Two Families of Transposable Sequences |
|
|
218 | (1) |
|
Viruses Are Fully Mobile Genetic Elements That Can Escape from Cells |
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|
219 | (2) |
|
Retroviruses Reverse the Normal Flow of Genetic Information |
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|
221 | (8) |
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From DNA to Protein: How Cells Read the Genome |
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|
229 | (38) |
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230 | (13) |
|
Portions of DNA Sequence Are Transcribed into RNA |
|
|
230 | (1) |
|
Transcription Produces RNA Complementary to One Strand of DNA |
|
|
231 | (2) |
|
Several Types of RNA Are Produced in Cells |
|
|
233 | (1) |
|
Signals in DNA Tell RNA Polymerase Where to Start and Finish |
|
|
234 | (2) |
|
Eucaryotic RNAs Are Transcribed and Processed Simultaneously in the Nucleus |
|
|
236 | (1) |
|
Eucaryotic Genes Are Interrupted by Noncoding Sequences |
|
|
237 | (1) |
|
Introns Are Removed by RNA Splicing |
|
|
238 | (3) |
|
Mature Eucaryotic mRNAs Are Selectively Exported from the Nucleus |
|
|
241 | (1) |
|
mRNA Molecules Are Eventually Degraded by the Cell |
|
|
242 | (1) |
|
The Earliest Cells May Have Had Introns in Their Genes |
|
|
242 | (1) |
|
|
243 | (15) |
|
An mRNA Sequence Is Decoded in Sets of Three Nucleotides |
|
|
244 | (1) |
|
tRNA Molecules Match Amino Acids to Codons in mRNA |
|
|
245 | (3) |
|
Specific Enzymes Couple tRNAs to the Correct Amino Acid |
|
|
248 | (1) |
|
The RNA Message Is Decoded on Ribosomes |
|
|
248 | (3) |
|
The Ribosome Is a Ribozyme |
|
|
251 | (2) |
|
Codons in mRNA Signal Where to Start and to Stop Protein Synthesis |
|
|
253 | (1) |
|
Proteins Are Made on Polyribosomes |
|
|
254 | (1) |
|
Inhibitors of Procaryotic Protein Synthesis Are Used as Antibiotics |
|
|
255 | (1) |
|
Carefully Controlled Protein Breakdown Helps Regulate the Amount of Each Protein in a Cell |
|
|
256 | (1) |
|
There Are Many Steps Between DNA and Protein |
|
|
257 | (1) |
|
RNA and the Origins of Life |
|
|
258 | (9) |
|
Life Requires Autocatalysis |
|
|
259 | (1) |
|
RNA Can Both Store Information and Catalyze Chemical Reactions |
|
|
259 | (2) |
|
RNA Is Thought to Predate DNA in Evolution |
|
|
261 | (6) |
|
Control of Gene Expression |
|
|
267 | (26) |
|
An Overview of Gene Expression |
|
|
268 | (3) |
|
The Different Cell Types of a Multicellular Organism Contain the Same DNA |
|
|
268 | (1) |
|
Different Cell Types Produce Different Sets of Proteins |
|
|
268 | (2) |
|
A Cell Can Change the Expression of Its Genes in Response to External Signals |
|
|
270 | (1) |
|
Gene Expression Can Be Regulated at Many of the Steps in the Pathway from DNA to RNA to Protein |
|
|
270 | (1) |
|
How Transcriptional Switches Work |
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|
271 | (9) |
|
Transcription Is Controlled by Proteins Binding to Regulatory DNA Sequences |
|
|
271 | (2) |
|
Repressors Turn Genes Off, Activators Turn Them On |
|
|
273 | (2) |
|
An Activator and a Repressor Control the Iac Operon |
|
|
275 | (1) |
|
Initiation of Eucaryotic Gene Transcription Is a Complex Process |
|
|
275 | (1) |
|
Eucaryotic RNA Polymerase Requires General Transcription Factors |
|
|
276 | (2) |
|
Eucaryotic Gene Regulatory Proteins Control Gene Expression from a Distance |
|
|
278 | (1) |
|
Packing of Promoter DNA into Nucleosomes Can Affect Initiation of Transcription |
|
|
279 | (1) |
|
The Molecular Mechanisms that Create Specialized Cell Types |
|
|
280 | (13) |
|
Eucaryotic Genes Are Regulated by Combinations of Proteins |
|
|
281 | (1) |
|
The Expression of Different Genes Can Be Coordinated by a Single Protein |
|
|
281 | (4) |
|
Combinatorial Control Can Create Different Cell Types |
|
|
285 | (1) |
|
Stable Patterns of Gene Expression Can Be Transmitted to Daughter Cells |
|
|
286 | (2) |
|
The Formation of an Entire Organ Can Be Triggered by a Single Gene Regulatory Protein |
|
|
288 | (5) |
|
How Genes and Genomes Evolve |
|
|
293 | (30) |
|
Generating Genetic Variation |
|
|
293 | (11) |
|
Five Main Types of Genetic Change Contribute to Evolution |
|
|
295 | (1) |
|
Genome Alterations Are Caused by Failures of the Normal Mechanisms for Copying and Maintaining DNA |
|
|
296 | (1) |
|
DNA Duplications Give Rise to Families of Related Genes Within a Single Cell |
|
|
297 | (1) |
|
The Evolution of the Globin Gene Family Shows How DNA Duplications Contribute to the Evolution of Organisms |
|
|
298 | (1) |
|
Gene Duplication and Divergence Provide a Critical Source of Genetic Novelty for Evolving Organisms |
|
|
299 | (1) |
|
New Genes Can Be Generated by Repeating the Same Exon |
|
|
300 | (1) |
|
Novel Genes Can Also Be Created by Exon Shuffling |
|
|
300 | (1) |
|
The Evolution of Genomes Has Been Accelerated by the Movement of Transposable Elements |
|
|
301 | (1) |
|
Genes Can Be Exchanged Between Organisms by Horizontal Gene Transfer |
|
|
302 | (2) |
|
Reconstructing Life's Family Tree |
|
|
304 | (7) |
|
Genetic Changes That Offer an Organism a Selective Advantage Are the Most Likely to Be Preserved |
|
|
304 | (1) |
|
The Genome Sequences of Two Species Differ in Proportion to the Length of Time That They Have Evolved Separately |
|
|
305 | (1) |
|
Humans and Chimpanzee Genomes Are Similar in Organization as Well as Detailed Sequence |
|
|
306 | (1) |
|
Functionally Important Sequences Show Up as Islands of DNA Sequence Conservation |
|
|
307 | (1) |
|
Genome Comparisons Suggest That ``Junk DNA'' is Dispensable |
|
|
308 | (1) |
|
Sequence Conservation Allows Us to Trace Even the Most Distant Evolutionary Relationships |
|
|
309 | (2) |
|
Examining the Human Genome |
|
|
311 | (12) |
|
The Nucleotide Sequence of the Human Genome Shows How Our Genes Are Arranged |
|
|
311 | (2) |
|
Genetic Variation Within the Human Genome Contributes to Our Individuality |
|
|
313 | (3) |
|
Comparing Our DNA with That of Related Organisms Helps Us to Interpret the Human Genome |
|
|
316 | (1) |
|
The Human Genome Contains Copious Information Yet to Be Deciphered |
|
|
317 | (6) |
|
Manipulating Genes and Cells |
|
|
323 | (42) |
|
Isolating Cells and Growing Them in Culture |
|
|
324 | (3) |
|
A Uniform Population of Cells Can Be Obtained from a Tissue |
|
|
325 | (1) |
|
Cells Can Be Grown in a Culture Dish |
|
|
325 | (1) |
|
Maintaining Eucaryotic Cells in Culture Poses Special Challenges |
|
|
326 | (1) |
|
How DNA Molecules Are Analyzed |
|
|
327 | (9) |
|
Restriction Nucleases Cut DNA Molecules at Specific Sites |
|
|
328 | (1) |
|
Gel Electrophoresis Separates DNA Fragments of Different Sizes |
|
|
329 | (2) |
|
The Nucleotide Sequence of DNA Fragments Can Be Determined |
|
|
331 | (2) |
|
Genome Sequences Are Searched to Identify Genes |
|
|
333 | (3) |
|
Nucleic Acid Hybridization |
|
|
336 | (5) |
|
DNA Hybridization Facilitates the Diagnosis of Genetic Diseases |
|
|
336 | (2) |
|
Hybridization on DNA Microarrays Monitors the Expression of Thousands of Genes at Once |
|
|
338 | (2) |
|
In Situ Hybridization Locates Nucleic Acid Sequences in Cells or on Chromosomes |
|
|
340 | (1) |
|
|
341 | (11) |
|
DNA Ligase Joins DNA Fragments Together to Produce a Recombinant DNA Molecule |
|
|
341 | (1) |
|
Recombinant DNA Can Be Copied Inside Bacterial Cells |
|
|
341 | (1) |
|
Specialized Plasmid Vectors Are Used to Clone DNA |
|
|
342 | (1) |
|
Human Genes Are Isolated by DNA Cloning |
|
|
343 | (3) |
|
cDNA Libraries Represent the mRNA Produced by a Particular Tissue |
|
|
346 | (1) |
|
The Polymerase Chain Reaction Amplifies Selected DNA Sequences |
|
|
347 | (5) |
|
|
352 | (13) |
|
Completely Novel DNA Molecules Can Be Constructed |
|
|
352 | (1) |
|
Rare Cellular Proteins Can Be Made in Large Amounts Using Cloned DNA |
|
|
352 | (1) |
|
Engineered Genes Can Reveal When and Where a Gene Is Expressed |
|
|
353 | (2) |
|
Mutant Organisms Best Reveal the Function of a Gene |
|
|
355 | (1) |
|
Animals Can Be Genetically Altered |
|
|
356 | (3) |
|
Transgenic Plants Are Important for Both Cell Biology and Agriculture |
|
|
359 | (6) |
|
|
365 | (24) |
|
|
366 | (8) |
|
Membrane Lipids Form Bilayers in Water |
|
|
367 | (3) |
|
The Lipid Bilayer Is a Two-dimensional Fluid |
|
|
370 | (1) |
|
The Fluidity of a Lipid Bilayer Depends on Its Composition |
|
|
371 | (2) |
|
The Lipid Bilayer Is Asymmetrical |
|
|
373 | (1) |
|
Lipid Asymmetry Is Generated Inside the Cell |
|
|
373 | (1) |
|
|
374 | (15) |
|
Membrane Proteins Associate with the Lipid Bilayer in Various Ways |
|
|
375 | (1) |
|
A Polypeptide Chain Usually Crosses the Bilayer as an α Helix |
|
|
376 | (1) |
|
Membrane Proteins Can Be Solubilized in Detergents and Purified |
|
|
377 | (1) |
|
The Complete Structure Is Known for a Few Membrane Proteins |
|
|
378 | (2) |
|
The Plasma Membrane Is Reinforced by the Cell Cortex |
|
|
380 | (1) |
|
The Cell Surface Is Coated with Carbohydrate |
|
|
381 | (2) |
|
Cells Can Restrict the Movement of Membrane Proteins |
|
|
383 | (6) |
|
|
389 | (38) |
|
Principles of Membrane Transport |
|
|
389 | (4) |
|
The Ion Concentrations Inside a Cell Are Very Different from Those Outside |
|
|
390 | (1) |
|
Lipid Bilayers Are Impermeable to Solutes and Ions |
|
|
391 | (1) |
|
Membrane Transport Proteins Fall into Two Classes: Carriers and Channels |
|
|
391 | (1) |
|
Solutes Cross Membranes by Passive or Active Transport |
|
|
392 | (1) |
|
Carrier Proteins and Their Functions |
|
|
393 | (10) |
|
Concentration Gradients and Electrical Forces Drive Passive Transport |
|
|
393 | (2) |
|
Active Transport Moves Solutes Against Their Electrochemical Gradients |
|
|
395 | (1) |
|
Animal Cells Use the Energy of ATP Hydrolysis to Pump Out Na+ |
|
|
396 | (1) |
|
The Na+-K+ Pump Is Driven by the Transient Addition of a Phosphate Group |
|
|
397 | (1) |
|
Animal Cells Use the Na+ Gradient to Take Up Nutrients Actively |
|
|
397 | (2) |
|
The Na+-K+ Pump Helps Maintain the Osmotic Balance of Animal Cells |
|
|
399 | (2) |
|
Intracellular Ca2+ Concentrations Are Kept Low by Ca2+ Pumps |
|
|
401 | (1) |
|
H+ Gradients Are Used to Drive Membrane Transport in Plants, Fungi, and Bacteria |
|
|
402 | (1) |
|
Ion Channels and the Membrane Potential |
|
|
403 | (8) |
|
Ion Channels Are Ion-Selective and Gated |
|
|
403 | (2) |
|
Ion Channels Randomly Snap Between Open and Closed States |
|
|
405 | (2) |
|
Different Types of Stimuli Influence the Opening and Closing of Ion Channels |
|
|
407 | (1) |
|
Voltage-gated Ion Channels Respond to the Membrane Potential |
|
|
407 | (1) |
|
Membrane Potential Is Governed by Membrane Permeability to Specific Ions |
|
|
408 | (3) |
|
Ion Channels and Signaling in Nerve Cells |
|
|
411 | (16) |
|
Action Potentials Provide for Rapid Long-Distance Communication |
|
|
411 | (1) |
|
Action Potentials Are Usually Mediated by Voltage-gated Na+ Channels |
|
|
412 | (5) |
|
Voltage-gated Ca2+ Channels Convert Electrical Signals into Chemical Signals at Nerve Terminals |
|
|
417 | (1) |
|
Transmitter-gated Channels in Target Cells Convert Chemical Signals Back into Electrical Signals |
|
|
417 | (2) |
|
Neurons Receive Both Excitatory and Inhibitory Inputs |
|
|
419 | (1) |
|
Transmitter-gated Ion Channels Are Major Targets for Psychoactive Drugs |
|
|
419 | (1) |
|
Synaptic Connections Enable You to Think, Act, and Remember |
|
|
420 | (7) |
|
How Cells Obtain Energy from Food |
|
|
427 | (26) |
|
The Breakdown of Sugars and Fats |
|
|
428 | (16) |
|
Food Molecules Are Broken Down in Three Stages |
|
|
428 | (2) |
|
Glycolysis Is a Central ATP-producing Pathway |
|
|
430 | (1) |
|
Fermentations Allow ATP to Be Produced in the Absence of Oxygen |
|
|
431 | (3) |
|
Glycolysis Illustrates How Enzymes Couple Oxidation to Energy Storage |
|
|
434 | (1) |
|
Sugars and Fats Are Both Degraded to Acetyl CoA in Mitochondria |
|
|
435 | (4) |
|
The Citric Acid Cycle Generates NADH by Oxidizing Acetyl Groups to CO2 |
|
|
439 | (2) |
|
Electron Transport Drives the Synthesis of the Majority of the ATP in Most Cells |
|
|
441 | (3) |
|
Storing and Utilizing Food |
|
|
444 | (9) |
|
Organisms Store Food Molecules in Special Reservoirs |
|
|
444 | (2) |
|
Chloroplasts and Mitochondria Collaborate in Plant Cells |
|
|
446 | (1) |
|
Many Biosynthetic Pathways Begin with Glycolysis or the Citric Acid Cycle |
|
|
447 | (1) |
|
Metabolism Is Organized and Regulated |
|
|
448 | (5) |
|
Energy Generation in Mitochondria and Chloroplasts |
|
|
453 | (44) |
|
Cells Obtain Most of Their Energy by a Membrane-based Mechanism |
|
|
453 | (2) |
|
Mitochondria and Oxidative Phosphorylation |
|
|
455 | (13) |
|
A Mitochondrion Contains an Outer Membrane, an Inner Membrane, and Two Internal Compartments |
|
|
455 | (2) |
|
High-Energy Electrons Are Generated via the Citric Acid Cycle |
|
|
457 | (1) |
|
A Chemiosmotic Process Converts Oxidation Energy into ATP |
|
|
458 | (1) |
|
Electrons Are Transferred Along a Chain of Proteins in the Inner Mitochondrial Membrane |
|
|
459 | (3) |
|
Electron Transport Generates a Proton Gradient Across the Membrane |
|
|
462 | (2) |
|
The Proton Gradient Drives ATP Synthesis |
|
|
464 | (2) |
|
Coupled Transport Across the Inner Mitochondrial Membrane Is Driven by the Electrochemical Proton Gradient |
|
|
466 | (1) |
|
Proton Gradients Produce Most of the Cell's ATP |
|
|
466 | (2) |
|
The Rapid Conversion of ADP to ATP in Mitochondria Maintains a High ATP/ADP Ratio in Cells |
|
|
468 | (1) |
|
Electron-Transport Chains and Proton Pumping |
|
|
468 | (10) |
|
Protons Are Readily Moved by the Transfer of Electrons |
|
|
468 | (1) |
|
The Redox Potential Is a Measure of Electron Affinities |
|
|
469 | (1) |
|
Electron Transfers Release Large Amounts of Energy |
|
|
470 | (2) |
|
Metals Tightly Bound to Proteins Form Versatile Electron Carriers |
|
|
472 | (2) |
|
Cytochrome Oxidase Catalyzes Oxygen Reduction |
|
|
474 | (1) |
|
The Mechanism of H+ Pumping Will Soon Be Understood in Atomic Detail |
|
|
475 | (1) |
|
Respiration Is Amazingly Efficient |
|
|
476 | (2) |
|
Chloroplasts and Photosynthesis |
|
|
478 | (9) |
|
Chloroplasts Resemble Mitochondria but Have an Extra Compartment |
|
|
478 | (2) |
|
Chloroplasts Capture Energy from Sunlight and Use It to Fix Carbon |
|
|
480 | (1) |
|
Excited Chlorophyll Molecules Funnel Energy into a Reaction Center |
|
|
481 | (1) |
|
Light Energy Drives the Synthesis of ATP and NADPH |
|
|
482 | (3) |
|
Carbon Fixation Is Catalyzed by Ribulose Bisphosphate Carboxylase |
|
|
485 | (1) |
|
Carbon Fixation in Chloroplasts Generates Sucrose and Starch |
|
|
486 | (1) |
|
The Origins of Chloroplasts and Mitochondria |
|
|
487 | (10) |
|
Oxidative Phosphorylation Gave Ancient Bacteria an Evolutionary Advantage |
|
|
488 | (1) |
|
Photosynthetic Bacteria Made Even Fewer Demands on Their Environment |
|
|
489 | (1) |
|
The Lifestyle of Methanococcus Suggests That Chemiosmotic Coupling Is an Ancient Process |
|
|
490 | (7) |
|
Intracellular Compartments and Transport |
|
|
497 | (36) |
|
Membrane-enclosed Organelles |
|
|
498 | (4) |
|
Eucaryotic Cells Contain a Basic Set of Membrane-enclosed Organelles |
|
|
498 | (2) |
|
Membrane-enclosed Organelles Evolved in Different Ways |
|
|
500 | (2) |
|
|
502 | (10) |
|
Proteins Are Imported into Organelles by Three Mechanisms |
|
|
502 | (1) |
|
Signal Sequences Direct Proteins to the Correct Compartment |
|
|
503 | (1) |
|
Proteins Enter the Nucleus Through Nuclear Pores |
|
|
504 | (2) |
|
Proteins Unfold to Enter Mitochondria and Chloroplasts |
|
|
506 | (1) |
|
Proteins Enter the Endoplasmic Reticulum While Being Synthesized |
|
|
507 | (2) |
|
Soluble Proteins Are Released into the ER Lumen |
|
|
509 | (1) |
|
Start and Stop Signals Determine the Arrangement of a Transmembrane Protein in the Lipid Bilayer |
|
|
510 | (2) |
|
|
512 | (4) |
|
Transport Vesicles Carry Soluble Proteins and Membrane Between Compartments |
|
|
512 | (1) |
|
Vesicle Budding Is Driven by the Assembly of a Protein Coat |
|
|
513 | (2) |
|
The Specificity of Vesicle Docking Depends on SNAREs |
|
|
515 | (1) |
|
|
516 | (7) |
|
Most Proteins Are Covalently Modified in the ER |
|
|
516 | (1) |
|
Exit from the ER Is Controlled to Ensure Protein Quality |
|
|
517 | (1) |
|
Proteins Are Further Modified and Sorted in the Golgi Apparatus |
|
|
518 | (1) |
|
Secretory Proteins Are Released from the Cell by Exocytosis |
|
|
519 | (4) |
|
|
523 | (10) |
|
Specialized Phagocytic Cells Ingest Large Particles |
|
|
523 | (2) |
|
Fluid and Macromolecules Are Taken Up by Pinocytosis |
|
|
525 | (1) |
|
Receptor-mediated Endocytosis Provides a Specific Route into Animal Cells |
|
|
525 | (1) |
|
Endocytosed Macromolecules Are Sorted in Endosomes |
|
|
526 | (1) |
|
Lysosomes Are the Principal Sites of Intracellular Digestion |
|
|
527 | (6) |
|
|
533 | (40) |
|
General Principles of Cell Signaling |
|
|
533 | (13) |
|
Signals Can Act over Long or Short Range |
|
|
534 | (2) |
|
Each Cell Responds to a Limited Set of Signals |
|
|
536 | (2) |
|
Receptors Relay Signals via Intracellular Signaling Pathways |
|
|
538 | (2) |
|
Nitric Oxide Crosses the Plasma Membrane and Activates Intracellular Enzymes Directly |
|
|
540 | (1) |
|
Some Hormones Cross the Plasma Membrane and Bind to Intracellular Receptors |
|
|
541 | (1) |
|
Cell-Surface Receptors Fall into Three Main Classes |
|
|
542 | (2) |
|
Ion-channel--linked Receptors Convert Chemical Signals into Electrical Ones |
|
|
544 | (1) |
|
Many Intracellular Signaling Proteins Act as Molecular Switches |
|
|
545 | (1) |
|
G-protein--linked Receptors |
|
|
546 | (11) |
|
Stimulation of G-protein--linked Receptors Activates G-Protein Subunits |
|
|
546 | (2) |
|
Some G Proteins Regulate Ion Channels |
|
|
548 | (1) |
|
Some G Proteins Activate Membrane-bound Enzymes |
|
|
549 | (1) |
|
The Cyclic AMP Pathway Can Activate Enzymes and Turn On Genes |
|
|
550 | (2) |
|
The Inositol Phospholipid Pathway Triggers a Rise in Intracellular Ca2+ |
|
|
552 | (2) |
|
A Ca2+ Signal Triggers Many Biological Processes |
|
|
554 | (1) |
|
Intracellular Signaling Cascades Can Achieve Astonishing Speed, Sensitivity, and Adaptability: A Look at Photoreceptors in the Eye |
|
|
555 | (2) |
|
|
557 | (16) |
|
Activated Receptor Tyrosine Kinases Assemble a Complex of Intracellular Signaling Proteins |
|
|
557 | (2) |
|
Receptor Tyrosine Kinases Activate the GTP-binding Protein Ras |
|
|
559 | (1) |
|
Some Enzyme-linked Receptors Activate a Fast Track to the Nucleus |
|
|
560 | (5) |
|
Protein Kinase Networks Integrate Information to Control Complex Cell Behaviors |
|
|
565 | (1) |
|
Multicellularity and Cell Communication Evolved Independently in Plants and Animals |
|
|
566 | (7) |
|
|
573 | (38) |
|
|
574 | (5) |
|
Intermediate Filaments Are Strong and Ropelike |
|
|
575 | (1) |
|
Intermediate Filaments Strengthen Cells Against Mechanical Stress |
|
|
576 | (2) |
|
The Nuclear Envelope Is Supported by a Meshwork of Intermediate Filaments |
|
|
578 | (1) |
|
|
579 | (13) |
|
Microtubules Are Hollow Tubes with Structurally Distinct Ends |
|
|
579 | (1) |
|
The Centrosome Is the Major Microtubule-organizing Center in Animal Cells |
|
|
580 | (1) |
|
Growing Microtubules Show Dynamic Instability |
|
|
581 | (1) |
|
Microtubules Are Maintained by a Balance of Assembly and Disassembly |
|
|
582 | (1) |
|
Microtubules Organize the Interior of the Cell |
|
|
583 | (1) |
|
Motor Proteins Drive Intracellular Transport |
|
|
584 | (1) |
|
Organelles Move Along Microtubules |
|
|
585 | (5) |
|
Cilia and Flagella Contain Stable Microtubules Moved by Dynein |
|
|
590 | (2) |
|
|
592 | (8) |
|
Actin Filaments Are Thin and Flexible |
|
|
593 | (1) |
|
Actin and Tubulin Polymerize by Similar Mechanisms |
|
|
593 | (1) |
|
Many Proteins Bind to Actin and Modify Its Properties |
|
|
594 | (1) |
|
An Actin-rich Cortex Underlies the Plasma Membrane of Most Eucaryotic Cells |
|
|
594 | (1) |
|
Cell Crawling Depends on Actin |
|
|
595 | (3) |
|
Actin Associates with Myosin to Form Contractile Structures |
|
|
598 | (1) |
|
Extracellular Signals Control the Arrangement of Actin Filaments |
|
|
599 | (1) |
|
|
600 | (11) |
|
Muscle Contraction Depends on Bundles of Actin and Myosin |
|
|
600 | (1) |
|
During Muscle Contraction Actin Filaments Slide Against Myosin Filaments |
|
|
601 | (2) |
|
Muscle Contraction Is Triggered by a Sudden Rise in Ca2+ |
|
|
603 | (2) |
|
Muscle Cells Perform Highly Specialized Functions in the Body |
|
|
605 | (6) |
|
Cell-Cycle Control and Cell Death |
|
|
611 | (26) |
|
Overview of the Cell Cycle |
|
|
612 | (3) |
|
The Eucaryotic Cell Cycle Is Divided into Four Phases |
|
|
613 | (1) |
|
A Central Control System Triggers the Major Processes of the Cell Cycle |
|
|
614 | (1) |
|
The Cell-Cycle Control System |
|
|
615 | (10) |
|
The Cell-Cycle Control System Depends on Cyclically Activated Protein Kinases |
|
|
616 | (1) |
|
Cyclin-dependent Protein Kinases Are Regulated by the Accumulation and Destruction of Cyclins |
|
|
617 | (1) |
|
The Activity of Cdks Is Also Regulated by Phosphorylation and Dephosphorylation |
|
|
617 | (3) |
|
Different Cyclin-Cdk Complexes Trigger Different Steps in the Cell Cycle |
|
|
620 | (1) |
|
S-Cdk Initiates DNA Replication and Helps Block Rereplication |
|
|
621 | (1) |
|
Cdks Are Inactive Through Most of G1 |
|
|
622 | (1) |
|
The Cell-Cycle Control System Can Arrest the Cycle at Specific Checkpoints |
|
|
622 | (2) |
|
Cells Can Dismantle Their Control System and Withdraw from the Cell Cycle |
|
|
624 | (1) |
|
Programmed Cell Death (Apoptosis) |
|
|
625 | (3) |
|
Apoptosis Is Mediated by an Intracellular Proteolytic Cascade |
|
|
626 | (1) |
|
The Death Program Is Regulated by the Bcl-2 Family of Intracellular Proteins |
|
|
627 | (1) |
|
Extracellular Control of Cell Numbers and Cell Size |
|
|
628 | (9) |
|
Animal Cells Require Extracellular Signals to Divide, Grow, and Survive |
|
|
629 | (1) |
|
Mitogens Stimulate Cell Division |
|
|
629 | (2) |
|
Extracellular Growth Factors Stimulate Cells to Grow |
|
|
631 | (1) |
|
Animal Cells Require Survival Factors to Avoid Apoptosis |
|
|
631 | (1) |
|
Some Extracellular Signal Proteins Inhibit Cell Growth, Division, or Survival |
|
|
632 | (5) |
|
|
637 | (22) |
|
|
638 | (3) |
|
In Preparation for M Phase, DNA-binding Proteins Configure Replicated Chromosomes for Segregation |
|
|
638 | (1) |
|
The Cytoskeleton Carries Out Both Mitosis and Cytokinesis |
|
|
639 | (1) |
|
Centrosomes Duplicate To Help Form the Two Poles of the Mitotic Spindle |
|
|
640 | (1) |
|
M Phase Is Conventionally Divided into Six Stages |
|
|
640 | (1) |
|
|
641 | (11) |
|
Microtubule Instability Facilitates the Formation of the Mitotic Spindle |
|
|
641 | (3) |
|
The Mitotic Spindle Starts to Assemble in Prophase |
|
|
644 | (1) |
|
Chromosomes Attach to the Mitotic Spindle at Prometaphase |
|
|
645 | (3) |
|
Chromosomes Line Up at the Spindle Equator at Metaphase |
|
|
648 | (1) |
|
Daughter Chromosomes Segregate at Anaphase |
|
|
649 | (2) |
|
The Nuclear Envelope Re-forms at Telophase |
|
|
651 | (1) |
|
Some Organelles Fragment at Mitosis |
|
|
651 | (1) |
|
|
652 | (7) |
|
The Mitotic Spindle Determines the Plane of Cytoplasmic Cleavage |
|
|
652 | (1) |
|
The Contractile Ring of Animal Cells Is Made of Actin and Myosin |
|
|
653 | (1) |
|
Cytokinesis in Plant Cells Involves New Cell-Wall Formation |
|
|
654 | (1) |
|
Gametes Are Formed by a Specialized Kind of Cell Division |
|
|
655 | (4) |
|
Genetics, Meiosis, and the Molecular Basis of Heredity |
|
|
659 | (38) |
|
|
660 | (3) |
|
Sexual Reproduction Involves Both Diploid and Haploid Cells |
|
|
661 | (1) |
|
Sexual Reproduction Gives Organisms a Competitive Advantage |
|
|
662 | (1) |
|
|
663 | (9) |
|
Haploid Cells Are Produced From Diploid Cells Through Meiosis |
|
|
664 | (1) |
|
Meiosis Involves a Special Process of Chromosome Pairing |
|
|
664 | (1) |
|
Extensive Recombination Occurs Between Maternal and Paternal Chromosomes |
|
|
665 | (2) |
|
Chromosome Pairing and Recombination Ensure the Proper Segregation of Homologs |
|
|
667 | (1) |
|
The Second Meiotic Division Produces Haploid Daughter Cells |
|
|
667 | (1) |
|
The Haploid Cells Contain Extensively Reassorted Genetic Information |
|
|
668 | (2) |
|
|
670 | (1) |
|
Fertilization Reconstitutes a Complete Genome |
|
|
671 | (1) |
|
Mendel and the Laws of Inheritance |
|
|
672 | (14) |
|
Mendel Chose to Study Traits That Are Inherited in a Discrete Fashion |
|
|
673 | (1) |
|
Mendel Could Disprove the Alternative Theories of Inheritance |
|
|
674 | (1) |
|
Mendel's Experiments Were the First to Reveal the Discrete Nature of Heredity |
|
|
674 | (1) |
|
Each Gamete Carries a Single Allele for Each Character |
|
|
675 | (1) |
|
Mendel's Law of Segregation Applies to All Sexually Reproducing Organisms |
|
|
676 | (1) |
|
Alleles for Different Traits Segregate Independently |
|
|
677 | (1) |
|
The Behavior of Chromosomes During Meiosis Underlies Mendel's Laws of Inheritance |
|
|
678 | (2) |
|
The Frequency of Recombination Can Be Used to Order Genes on Chromosomes |
|
|
680 | (1) |
|
The Phenotype of the Heterozygote Reveals Whether an Allele is Dominant or Recessive |
|
|
681 | (3) |
|
Mutant Alleles Sometimes Confer a Selective Advantage |
|
|
684 | (2) |
|
Genetics as an Experimental Tool |
|
|
686 | (11) |
|
The Classical Approach Begins with Random Mutagenesis |
|
|
686 | (1) |
|
Genetic Screens Identify Mutants Deficient in Cellular Processes |
|
|
687 | (1) |
|
A Complementation Test Reveals Whether Two Mutations Are in the Same Gene |
|
|
688 | (1) |
|
Human Genes Are Inherited in Haplotype Blocks, Which Can Aid in the Search for Mutations That Cause Disease |
|
|
689 | (2) |
|
Complex Traits Are Influenced by Multiple Genes |
|
|
691 | (1) |
|
Is Our Fate Encoded in Our DNA? |
|
|
692 | (5) |
|
|
697 | (1) |
|
Extracellular Matrix and Connective Tissues |
|
|
698 | (1) |
|
Plant Cells Have Tough External Walls |
|
|
698 | (4) |
|
Cellulose Fibers Give the Plant Cell Wall Its Tensile Strength |
|
|
702 | (1) |
|
Animal Connective Tissues Consist Largely of Extracellular Matrix |
|
|
703 | (1) |
|
Collagen Provides Tensile Strength in Animal Connective Tissues |
|
|
704 | (1) |
|
Cells Organize the Collagen That They Secrete |
|
|
705 | (1) |
|
Integrins Couple the Matrix Outside a Cell to the Cytoskeleton Inside It |
|
|
706 | (1) |
|
Gels of Polysaccharide and Protein Fill Spaces and Resist Compression |
|
|
706 | (3) |
|
Epithelial Sheets and Cell-Cell Junctions |
|
|
709 | (1) |
|
Epithelial Sheets Are Polarized and Rest on a Basal Lamina |
|
|
709 | (2) |
|
Tight Junctions Make an Epithelium Leak-proof and Separate Its Apical and Basal Surfaces |
|
|
711 | (1) |
|
Cytoskeleton-linked Junctions Bind Epithelial Cells Robustly to One Another and to the Basal Lamina |
|
|
712 | (3) |
|
Gap Junctions Allow Ions and Small Molecules to Pass from Cell to Cell |
|
|
715 | (2) |
|
Tissue Maintenance and Renewal |
|
|
717 | (1) |
|
Tissues Are Organized Mixtures of Many Cell Types |
|
|
718 | (2) |
|
Different Tissues Are Renewed at Different Rates |
|
|
720 | (1) |
|
Stem Cells Generate a Continuous Supply of Terminally Differentiated Cells |
|
|
721 | (1) |
|
Stem Cells Can Be Used to Repair Damaged Tissues |
|
|
722 | (3) |
|
Nuclear Transplantation Provides a Way to Generate Personalized ES Cells: the Strategy of Therapeutic Cloning |
|
|
725 | (1) |
|
|
726 | (1) |
|
Cancer Cells Proliferate, Invade, and Metastasize |
|
|
726 | (1) |
|
Epidemiology Identifies Preventable Causes of Cancer |
|
|
727 | (1) |
|
Cancers Develop by an Accumulation of Mutations |
|
|
728 | (1) |
|
Cancers Evolve Properties That Give Them a Competitive Advantage |
|
|
729 | (2) |
|
Many Diverse Types of Genes Are Critical for Cancer |
|
|
731 | (1) |
|
Colorectal Cancer Illustrates How Loss of a Gene Can Lead to Growth of a Tumor |
|
|
732 | (4) |
|
An Understanding of Cancer Cell Biology Opens the Way to New Treatments |
|
|
736 | |