Speaker:王姿文
Date:2016-01-22
view(s): 373
  • 00:09 1.
    6
  • 00:47 2.
    Overview: The Energy of Life
  • 00:25 3.
    Concept 6.1: An organism’s metabolism transforms matter and energy
  • 00:16 4.
    Metabolic Pathways
  • 00:30 5.
    Figure 6.UN01
  • 00:37 6.
    Catabolic pathways release energy by breaking down complex molecules into simpler compounds Cellular respiration, the breakdown of glucose in the presence of oxygen, is an example of a pathway of catabolism
  • 00:33 7.
    Anabolic pathways consume energy to build complex molecules from simpler ones The synthesis of protein from amino acids is an example of anabolism Bioenergetics is the study of how organisms manage their energy resources
  • 00:14 8.
    Forms of Energy
  • 01:18 9.
    Kinetic energy is energy associated with motion Thermal energy is kinetic energy associated with random movement of atoms or molecules Heat is thermal energy in transfer from one object to another Potential energy is energy that matter possesses because o
  • 01:11 10.
    Figure 6.2
  • 01:22 11.
    The Laws of Energy Transformation
  • 00:40 12.
    The First Law of Thermodynamics
  • 00:46 13.
    Figure 6.3
  • 00:44 14.
    The Second Law of Thermodynamics
  • 00:50 15.
    Living cells unavoidably convert organized forms of energy to heat Spontaneous processes occur without energy input; they can happen quickly or slowly For a process to occur without energy input, it must increase the entropy of the universe
  • 00:58 16.
    Biological Order and Disorder
  • 00:22 17.
    The evolution of more complex organisms does not violate the second law of thermodynamics Entropy (disorder) may decrease in an organism, but the universe’s total entropy increases Organisms are islands of low entropy in an increasingly random universe
  • 00:38 18.
    Concept 6.2: The free-energy change of a reaction tells us whether or not the reaction occurs spontaneously
  • 00:35 19.
    Free-Energy Change (G), Stability, and Equilibrium
  • 00:48 20.
    The change in free energy (∆G) during a chemical reaction is the difference between the free energy of the final state and the free energy of the initial state ∆G = Gfinal state – Ginitial state Only processes with a negative ∆G are spontaneous Spontaneou
  • 00:30 21.
    Free energy is a measure of a system’s instability, its tendency to change to a more stable state During a spontaneous change, free energy decreases and the stability of a system increases At equilibrium, forward and reverse reactions occur at the same ra
  • 01:15 22.
    Figure 6.5
  • 00:10 23.
    Free Energy and Metabolism
  • 01:11 24.
    Exergonic and Endergonic Reactions in Metabolism
  • 01:07 25.
    Figure 6.6
  • 00:48 26.
    Equilibrium and Metabolism
  • 00:02 27.
    A catabolic pathway in a cell releases free energy in a series of reactions Closed and open hydroelectric systems can serve as analogies
  • 01:56 28.
    Figure 6.7
  • 00:01 29.
    Concept 6.3: ATP powers cellular work by coupling exergonic reactions to endergonic reactions
  • 01:00 30.
    Concept 6.3: ATP powers cellular work by coupling exergonic reactions to endergonic reactions
  • 00:29 31.
    The Structure and Hydrolysis of ATP
  • 00:57 32.
    Figure 6.8
  • 00:23 33.
    The bonds between the phosphate groups of ATP can be broken by hydrolysis Energy is released from ATP when the terminal phosphate bond is broken This release of energy comes from the chemical change to a state of lower free energy, not from the phosphate
  • 00:12 34.
    How the Hydrolysis of ATP Performs Work
  • 02:55 35.
    Figure 6.9
  • 00:07 36.
    ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
  • 00:10 37.
    Figure 6.9
  • 00:02 38.
    ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
  • 02:07 39.
    Figure 6.10
  • 00:00 40.
    ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
  • 00:02 41.
    Figure 6.9
  • 00:00 42.
    ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
  • 00:00 43.
    Figure 6.10
  • 00:00 44.
    The Regeneration of ATP
  • 00:08 45.
    Figure 6.10
  • 00:30 46.
    The Regeneration of ATP
  • 00:54 47.
    Figure 6.11
  • 01:04 48.
    Concept 6.4: Enzymes speed up metabolic reactions by lowering energy barriers
  • 00:19 49.
    Figure 6.UN02
  • 01:29 50.
    The Activation Energy Barrier
  • 01:22 51.
    Figure 6.12
  • 00:07 52.
    How Enzymes Speed Up Reactions
  • 00:32 53.
    Figure 6.12
  • 00:04 54.
    How Enzymes Speed Up Reactions
  • 00:07 55.
    Slide 44
  • 00:34 56.
    Figure 6.13
  • 01:22 57.
    Substrate Specificity of Enzymes
  • 00:32 58.
    Enzymes change shape due to chemical interactions with the substrate This induced fit of the enzyme to the substrate brings chemical groups of the active site into positions that enhance their ability to catalyze the reaction
  • 00:53 59.
    Figure 6.14
  • 01:41 60.
    Catalysis in the Enzyme’s Active Site
  • 00:52 61.
    Figure 6.15-1
  • 00:28 62.
    Figure 6.15-2
  • 00:03 63.
    Figure 6.15-3
  • 00:22 64.
    Figure 6.15-4
  • 00:37 65.
    Effects of Local Conditions on Enzyme Activity
  • 00:09 66.
    Effects of Temperature and pH
  • 02:01 67.
    Figure 6.16
  • 00:57 68.
    Cofactors
  • 01:17 69.
    Enzyme Inhibitors
  • 01:26 70.
    Figure 6.17
  • 01:44 71.
    The Evolution of Enzymes
  • 00:03 72.
    Concept 6.5: Regulation of enzyme activity helps control metabolism
  • 00:29 73.
    Concept 6.5: Regulation of enzyme activity helps control metabolism
  • 00:38 74.
    Allosteric Regulation of Enzymes
  • 00:28 75.
    Allosteric Activation and Inhibition
  • 02:33 76.
    Figure 6.18
  • 00:06 77.
    Cooperativity is a form of allosteric regulation that can amplify enzyme activity One substrate molecule primes an enzyme to act on additional substrate molecules more readily Cooperativity is allosteric because binding by a substrate to one active site a
  • 00:26 78.
    Feedback Inhibition
  • 02:15 79.
    Figure 6.19
  • 00:39 80.
    Specific Localization of Enzymes Within the Cell
  • 00:31 81.
    Figure 6.20
  • Index
  • Notes
  • Discuss
  • Fullscreen
metabolism
Duration: 59:26, Browse: 373, Update: 2020-08-24
    • 00:09 1.
      6
    • 00:47 2.
      Overview: The Energy of Life
    • 00:25 3.
      Concept 6.1: An organism’s metabolism transforms matter and energy
    • 00:16 4.
      Metabolic Pathways
    • 00:30 5.
      Figure 6.UN01
    • 00:37 6.
      Catabolic pathways release energy by breaking down complex molecules into simpler compounds Cellular respiration, the breakdown of glucose in the presence of oxygen, is an example of a pathway of catabolism
    • 00:33 7.
      Anabolic pathways consume energy to build complex molecules from simpler ones The synthesis of protein from amino acids is an example of anabolism Bioenergetics is the study of how organisms manage their energy resources
    • 00:14 8.
      Forms of Energy
    • 01:18 9.
      Kinetic energy is energy associated with motion Thermal energy is kinetic energy associated with random movement of atoms or molecules Heat is thermal energy in transfer from one object to another Potential energy is energy that matter possesses because o
    • 01:11 10.
      Figure 6.2
    • 01:22 11.
      The Laws of Energy Transformation
    • 00:40 12.
      The First Law of Thermodynamics
    • 00:46 13.
      Figure 6.3
    • 00:44 14.
      The Second Law of Thermodynamics
    • 00:50 15.
      Living cells unavoidably convert organized forms of energy to heat Spontaneous processes occur without energy input; they can happen quickly or slowly For a process to occur without energy input, it must increase the entropy of the universe
    • 00:58 16.
      Biological Order and Disorder
    • 00:22 17.
      The evolution of more complex organisms does not violate the second law of thermodynamics Entropy (disorder) may decrease in an organism, but the universe’s total entropy increases Organisms are islands of low entropy in an increasingly random universe
    • 00:38 18.
      Concept 6.2: The free-energy change of a reaction tells us whether or not the reaction occurs spontaneously
    • 00:35 19.
      Free-Energy Change (G), Stability, and Equilibrium
    • 00:48 20.
      The change in free energy (∆G) during a chemical reaction is the difference between the free energy of the final state and the free energy of the initial state ∆G = Gfinal state – Ginitial state Only processes with a negative ∆G are spontaneous Spontaneou
    • 00:30 21.
      Free energy is a measure of a system’s instability, its tendency to change to a more stable state During a spontaneous change, free energy decreases and the stability of a system increases At equilibrium, forward and reverse reactions occur at the same ra
    • 01:15 22.
      Figure 6.5
    • 00:10 23.
      Free Energy and Metabolism
    • 01:11 24.
      Exergonic and Endergonic Reactions in Metabolism
    • 01:07 25.
      Figure 6.6
    • 00:48 26.
      Equilibrium and Metabolism
    • 00:02 27.
      A catabolic pathway in a cell releases free energy in a series of reactions Closed and open hydroelectric systems can serve as analogies
    • 01:56 28.
      Figure 6.7
    • 00:01 29.
      Concept 6.3: ATP powers cellular work by coupling exergonic reactions to endergonic reactions
    • 01:00 30.
      Concept 6.3: ATP powers cellular work by coupling exergonic reactions to endergonic reactions
    • 00:29 31.
      The Structure and Hydrolysis of ATP
    • 00:57 32.
      Figure 6.8
    • 00:23 33.
      The bonds between the phosphate groups of ATP can be broken by hydrolysis Energy is released from ATP when the terminal phosphate bond is broken This release of energy comes from the chemical change to a state of lower free energy, not from the phosphate
    • 00:12 34.
      How the Hydrolysis of ATP Performs Work
    • 02:55 35.
      Figure 6.9
    • 00:07 36.
      ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
    • 00:10 37.
      Figure 6.9
    • 00:02 38.
      ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
    • 02:07 39.
      Figure 6.10
    • 00:00 40.
      ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
    • 00:02 41.
      Figure 6.9
    • 00:00 42.
      ATP drives endergonic reactions by phosphorylation, transferring a phosphate group to some other molecule, such as a reactant The recipient molecule is now called a phosphorylated intermediate ATP hydrolysis leads to a change in a protein’s shape and ofte
    • 00:00 43.
      Figure 6.10
    • 00:00 44.
      The Regeneration of ATP
    • 00:08 45.
      Figure 6.10
    • 00:30 46.
      The Regeneration of ATP
    • 00:54 47.
      Figure 6.11
    • 01:04 48.
      Concept 6.4: Enzymes speed up metabolic reactions by lowering energy barriers
    • 00:19 49.
      Figure 6.UN02
    • 01:29 50.
      The Activation Energy Barrier
    • 01:22 51.
      Figure 6.12
    • 00:07 52.
      How Enzymes Speed Up Reactions
    • 00:32 53.
      Figure 6.12
    • 00:04 54.
      How Enzymes Speed Up Reactions
    • 00:07 55.
      Slide 44
    • 00:34 56.
      Figure 6.13
    • 01:22 57.
      Substrate Specificity of Enzymes
    • 00:32 58.
      Enzymes change shape due to chemical interactions with the substrate This induced fit of the enzyme to the substrate brings chemical groups of the active site into positions that enhance their ability to catalyze the reaction
    • 00:53 59.
      Figure 6.14
    • 01:41 60.
      Catalysis in the Enzyme’s Active Site
    • 00:52 61.
      Figure 6.15-1
    • 00:28 62.
      Figure 6.15-2
    • 00:03 63.
      Figure 6.15-3
    • 00:22 64.
      Figure 6.15-4
    • 00:37 65.
      Effects of Local Conditions on Enzyme Activity
    • 00:09 66.
      Effects of Temperature and pH
    • 02:01 67.
      Figure 6.16
    • 00:57 68.
      Cofactors
    • 01:17 69.
      Enzyme Inhibitors
    • 01:26 70.
      Figure 6.17
    • 01:44 71.
      The Evolution of Enzymes
    • 00:03 72.
      Concept 6.5: Regulation of enzyme activity helps control metabolism
    • 00:29 73.
      Concept 6.5: Regulation of enzyme activity helps control metabolism
    • 00:38 74.
      Allosteric Regulation of Enzymes
    • 00:28 75.
      Allosteric Activation and Inhibition
    • 02:33 76.
      Figure 6.18
    • 00:06 77.
      Cooperativity is a form of allosteric regulation that can amplify enzyme activity One substrate molecule primes an enzyme to act on additional substrate molecules more readily Cooperativity is allosteric because binding by a substrate to one active site a
    • 00:26 78.
      Feedback Inhibition
    • 02:15 79.
      Figure 6.19
    • 00:39 80.
      Specific Localization of Enzymes Within the Cell
    • 00:31 81.
      Figure 6.20
    Location
    Folder name
    普通生物學
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    王姿文
    Division
    生科系
    Create
    2016-01-22 16:15:39
    Update
    2020-08-24 23:35:49
    Browse
    373
    Duration
    59:26