Review Questions

Cell going through anaphase Nerve cell Cell Schematic: Eukaryote ATP

Exam 2

  1. Schematically draw a plasma membrane-spanning protein. Include any components of membrane protein asymmetry you can think of.

  2. Describe the roles of the following in vesicular transport
    1. SRP
    2. Signal Sequence
    3. Bip
    4. SNARE's

  3. What is different yet similar about protein transport into the nucleus vs. into a mitochondrion

  4. What role(s) is/are cholesterol thought to play in our cell membranes?

  5. Besides the glycolipids, phospholipids, and sterols, what other class of lip[ids is important in cell membrane structure, and in what tissues are they most normally found?

  6. Is facilitated transprot active only, passive only, either?

  7. How is facilitated diffusion different from and similar to passive diffusion?

  8. Outline the differences between carrier proteins and channel proteins with respect to their roles in active/passive transport and with respect to their mechanisms of action.

  9. What biochemical reaction is necessary in order to keep anaerobic glycolysis going?

  10. Anaerobic glycolysis by itself is finite. Why in microorganisms that produce ethanol, and in use, when we produce lactic acid, is this set of reactions limited in duration

  11. Why is the input of 2 ATP a necessary part of glycolysis?

  12. Why is it necessary for pyruvate to be able to be carboxylated and decarboxylated?

  13. Explain why the Krebs Cycle is aerobic, strictly speaking.

  14. Name two functions of the high energy phosphate bond molecule produced by the Krebs Cycle. Name the direct link between Krebs and Oxidative Phosphorylation.

  15. Is the proton motive force created across the inner mitochondrial membrane an active or passive event?

  16. Why do electrons from FADH2 yeild less ATP than electrons from NADH?

  17. Ascorbate (a form of Vitamin C) consumption is critical in the prevention of scurvy. It has also been found that ascorbate can function as an electron donor that can donate at the level of cytochrome c of the electron transport chain under laboratory conditions. How many ATP could theoretically be produced by a molecule of ascorbate? Would it be correct to think that you could boost your ATP production by increasing your vitamin c intake?

  18. Rank 1-4 (fastest to slowest) the rates of passive diffusion across a cell membrane among the following molecules, and give a word or two for your reasoning.
    1. GTP
    2. H2O
    3. Cl-
    4. lactose

  19. PFK is a major control point of glycolysis. How is glycolysis controlled at this point in relation to the overall functions of the glycolytic pathway? Name the other two control points of glycolysis.