11. What are the three main phases of glucose breakdown in aerobic organisms? What is the end-product for the first of these phases? How is it used to start the second phase, and what are the end-products of this phase? To what molecules is energy transferred in these two phases? Which one provides more stored energy? What is the third phase in glucose metabolism, and what substances from the earlier steps are regenerated? What happens to the energy that is saved in this last phase?

12. What does the prime, instead of a superscript zero, signify in DG'?

13. What happens to the pyruvate produced by glycolysis, if the organism is aerobic and a plentiful supply of 0₂ is available? What happens to the pyruvate in yeast when it is denied oxygen? In which mode of operation does glycolysis produce more net energy?

14. What is the purpose of the first five steps in glycolysis? Why is ATP necessary? Are the products of these five steps more, or less, stable than the starting glucose?

15. What happens in the second half of glycolysis to produce energy? What is the important oxidation step that yields the largest quantity of free energy? How is this free energy saved?

16. What happens to pyruvate in human muscles if an insufficient supply Of 0₂ is present? How does this create distress, and how is the distress alleviated?

17. What is the purpose of the citric acid cycle? How do the products of glycolysis enter the cycle?

18. What elements of strategy or of chemical "logic" are common to the following three reactions: (a) the conversion of G3P to DPG during glycolysis, (b) the conversion of pyruvate to acetyl coenzyme A, and (c) the conversion of a-ketoglutarate to succinyl coenzyme A?

19. What ultimately happens to the C0₂ that is liberated during the citric acid cycle?