1. Compared to the periplasmic space (space between peptidoglycan and cell membrane), the inside of the bacterial cell:
A. is more positively charged and has a higher concentration of protons
B. is more negatively charged and has a lower concentration of proton
C. is more negatively charged and has a higher concentration of protons
D. is more positively charged and has a lower concentration of protons
2. Which of the following contribute to the proton motive force across the cell membrane?
A. a difference in pH only
B. a difference in pH and electrons
C. a difference in pH and electrical charge
D. a difference in electrons and electrical charge
E. a difference in electrical charge only
3. If a microorganism has access to plenty of nutrients, in general, metabolic pathways that are catabolic would be less active that those that are anabolic.
A. True
B. False
4. If the cell membrane were to be damaged or punctured, how would this affect proton motive force?
A. Proton motive force would decrease
B. Proton motive force would increase
C. Proton motive force would not change
5. If NADH levels in the cell decrease, this would cause TCA cycle flux to:
A. Decrease
B. Increase
C. Not change
6. Generally speaking, when the ATP/ADP ratio in the cell dramatically increases, catabolic pathways will be more active and anabolic pathways will be less active.
A. True
B. False
7. If you were to measure hexokinase activity, in a bacterial cell, you should find that its activity is _______ in the absence of nutrients compared to having an adequate supply of nutrients.
A. no different
B. higher
C. lower
8. Pyruvate dehydrogenase activity would be _____ if a cell is using small amounts of energy as opposed to large amounts of energy.
A. lower
B. no different
C. higher
9. Consider the following reaction: Lactate + NADH ---> Lactate + NAD+ + H+. In the chemical reaction above, _____ gets reduced
A. Pyruvate
B. NADH
C. Lactate
D. NAD+
10. In the reaction above, _____ gets oxidized
A. Pyruvate
B. NADH
C. Lactate
D. NAD+
11. All of the following are direct products of the TCA cycle, EXCEPT
A. pyruvate
B. NADH
C. GTP
D. FADH2
E. CO2
12. In comparison to glycolysis, starting with glucose, how would the net ATP yield change if the process were initiated with galactose?
A. Minus 2 ATP
B. Plus 1 ATP
C. Plus 2 ATP
D. No change
E. Minus 1 ATP
13. Which of the following are negative allosteric regulators of phosphofructokinase? Note, there are two answers.
A. AMP
B. Citrate
C. ADP
D. ATP
E. Fructose-2,6-bisphosphate
14. Which of the following is a covalent inhibitor of pyruvate kinase? Hint: Make sure you know the difference between covalent and allosteric regulation before answering this question.
A. Acetyl CoA
B. Fructose-1,6-bisphosphate
C. Protein kinase A
D. ATP
15. Suppose a bacterial cell were to use a molecule of fructose to produce energy, instead of glucose, through glycolysis. In comparison to glucose, how would the ATP yield be affected if fructose is converted to glyceraldehyde-3-phosphate?
A. Plus 1
B. Minus 1
C. Plus 2
D. Minus 2
E. No change
16. In place of glucose, suppose a bacterial cell had a molecule of palmitate to oxidize for energy. How many ATP molecules would be produced from the complete oxidation of palmitate? Show your work. Hint: You will need to learn how fatty acid oxidation works, and determine the number of carbons in palmitate.
17. Calculate and compare the number of ATP produced from glucose (a 6-carbon molecule) versus a hypothetical 6-carbon fatty acid. Show your work.
18. If you had a pound of fat and a pound of some carbohydrate, which would contain more energy?
A. pound of fat
B. pound of carbohydrate
C. they are the same
19. We reviewed several structures of the bacterial cell (Gram-Negative; Gram-Positive). Pick the one you consider to be the most important in terms of the survival of the cell. In 10 sentences or less, defend your selection. You don't necessarily have to choose one of the structures we have discussed.
20. Pretend you are talking to a 3rd grader. Explain glucose oxidation (from glycolysis all the way through ATP synthase) to a 3rd grader.