Chapter 6

  1. cellular respiration
    the aerobic harvesting of energy from sugar by muscle cells (or other cells)
  2. redox reaction
    • the movement of one molecule to another
    • (also known as oxidation-reduction reaction)
  3. oxidation
    the loss of electrons from one substance
  4. reduction
    the addition of electrons to another substance
  5. dehydrogenase
    an enzyme that plays a key role in the process of oxidizing glucose
  6. NAD+
    • a coenzyme that plays a key role in the process of oxidizing glucose
    • an organic molecule that cells make from vitamin niacin and use to shuttle electrons in redox reactions
  7. electron transport chain
    a series of electron carrier molecules that shuttle electrons during the redox reactions that release energy to make ATP
  8. Cellular Respiration
    stage 1:Glycolysis
    • begins respiration by breaking glucose into two molecules of a three-carbon compound called pyruvate
    • (supply the third stage of respiration with electrons)
  9. Cellular Respiration
    stage2:Citric Acid Cycle
    • completes the breakdown of glucose by decomposing a derivative of pyruvate to carbon dioxide
    • (supply the third stage of respiration with electrons)
  10. Cellular Respiration
    stage3:Oxidative Phosphorylation
    • involves the electron transport chain and the process of chemiosmosis
    • NADH and FADH2 shuttle electrons to the electron transport chain embedded in the inner mitochondrion membrane
    • uses energy released by downhill fall of electrons from NADH and FADH2 to O2 to phosphorylate ADP
  11. Chemiosmosis
    • energy-coupling mechanics that uses the energy of hydrogen ion (H+) gradients across membranes to phosphorylate ADP
    • powers most ATP synthesis in cells
  12. ATP Synthasase
    a cluster of several membrane proteins that function in chemiosmosis with adjacent electron transport chains, using the energy of hydrogen ion concentration gradient to make ATP
  13. Substrate-level Phosphorylation
    • an enzyme transfers a phosphate group from a phosphate molecule to ADP, forming ATP
    • produces a small amount of ATP in glycolysis and the citric acid cycle
  14. intermidiates
    compounds that form between the initial reactant , glucose, and the final product, pyruvate
  15. lactic acid fermentation
    the conversion of pyruvate to lactate with no release of carbon dioxide
  16. alcohol fermentation
    the formation of pyruvate from glycolysis to carbon dioxide and ethyl alcohol
  17. obligate anaerobes
    require anaerobic conditions and are poisoned by oxygen
  18. facultative anaerobe
    makes ATP either by fermentation or by oxidative phosphorylation, depending on whether O2 is available
Card Set
Chapter 6
Biology:How Cells Harvest Chemical Energy