Study Guide - Biochemistry, The Molecular Basis of Life, 4th Ed., 2009, T. & J.R. McKee (Oxford Univ. Press)
Chapter 9: Citric Acid Cycle = Krebs Cycle
You can go back to the Fall, Spring or Summer schedules, to information on the lab , to the extra credit puzzles , or leave me a message . Or skip to ET/Ox. Phos. section or chapter 11 .
Why is the KC described as amphibolic? Determine where within the mitochondrial structure (matrix, cristae and intermembrane space) each pathway occurs in cellular respiration.
Where in the KC are the three carbons of pyruvate oxidized to CO2 and released? What coenzymes are generated and where in the cycle? What nucleotide triphosphate is generated and where?
What is the net reaction for one cycle starting with pyruvate? ...for just the KC starting with acetyl-CoA? ...for glycolysis and the KC?
How are vitamins and coenzymes related? What coenzymes are involved in the pyruvate (or alpha-ketoglutarate) dehydrogenase complex? What vitamins are essential for these steps to function?
What molecules function as allosteric regulators of the KC? Where and how do they work? How is this related to the energy charge of the cell?Which organisms have and do not have the glyoxylate cycle? What can the former do that the latter cannot?
The complete oxidation of glucose produces CO2, H2 O and ATP (how many of each?). Which pathways in cellular respiration produce each of these products?
Name the cofactors and coenzymes in each respiratory complex of the electron transport chain and the order in which they function.
Which cofactors reduced in the KC are oxidized, and where, in the ET chain? How many ATPs result from each?
Where is O2 reduced to H2O? What common poisons inhibit this reaction? ...and the ET chain in general?
What is the chemiosmotic coupling (Mitchell) hypothesis? How is this proton pumping of the ET chain and the pH and charge gradient that results like an electrical capacitor? What compounds can uncouple ET from Ox. Phos.?What is the net result of the aerobic respiration of glucose? ...of pyruvate?
Note Biochemical Connections, pg. 558 & 563.
End of chapter review questions: 1.-5. 15.-43. 49.