Catabolism

1. In a eukaryotic cell, what percentage of the ATPs made from the complete oxidation of glucose are produced by oxidative phosphorylation?
a. 100%
b. 94%
c. 88%
d. 12%
e. 0%

2. Which of the following is not an end product of fermentation?
a. Acetone
b. ATP
c. Butryic acid
d. Ethyl alcohol
e. Lactic acid

3. The antibiotic antimycin blocks the flow of electrons between cytochromes b and C. Why isn't antimycin used to treat bacterial diseases?
a. Bacteria don't have mitochondria
b. Bacteria don't have cytochromes b and c
c. Antimycin is toxic to human cells
d. Cells would switch to glycolysis
e. None of the above

4. How many molecules of carbon dioxide will be given off if you supply an aerobic cell with 5 pyruvic acid molecules?
a. 5
b. 10
c. 15
d. 20
e. 34

5. For a cell, which of the following compounds has the greatest amount of energy per molecule?
a. ATP
b. ADP
c. NADH
d. Molecular oxygen
e. Acetyl CoA

6. Which stage produces the most ATP?
a. Glycolysis
b. Production of acetyl CoA
c. Krebs cycle
d. Oxidative phosphorylation
e. Fermentation

7. 500 molecules of C-14 labelled glucose are given to yeast cells that are producing alcohol. How many molecules of C-14 labelled ATP can be mde from this glucose?
a. 0
b. 2
c. 4
d. 400
e. 2000

8. Your biotechnology company is growing a large volume of cells but they are not producing the desired product because the medium is too acidic. What is probably wrong?
a. The cells are producing too much ATP
b. Glycolysis is not occurring
c. There is too little molecular oxygen in the medium
d. The cells are using the Krebs cycle
e. There is too much sugar in the medium

9. What source of energy is used to move protons in chemiosmosis?
a. Protons push each other along
b. Active tranport
c. Oxidation of carriers
d. Energy from ATP
e. No energy is required since the process is exergonic

10. Red blood cells lack mitochondria. When a red blood cell is metabolizing glucose all of the following substances are produced except:
a. Lactic acid
b. Phosphoglyceraldehyde
c. Acetyl CoA
d. Pyruvic acid
e. ATP

11. The enzymes of glycolysis are located:
a. On the inner surface of the plasma membrane
b. In the cytosol
c. In the inner membrane of the mitochondrion
d. In the peroxisomes
e. In the Golgi apparatus

12. The presence of oxygen inhibits glycolysis at phosphofructokinase. The mechanism of inhibtion is:
a. Allosteric inhibition by AMP
b. Feedback inhibition by pyruvic acid
c. Competitive inhibition by lactic acid
d. Allosteric inhibition by ATP
e. Lack of fructose

13. The purpose of fermentation is to:
a. Prevent oxidative phosphorylation
b. Produce alcohol
c. Oxidize NADH
d. Produce glucose
e. Produce pyruvate

14. How much molecular oxygen is required in the fermentation of one molecule of glucose?
a. None
b. 1 molecule
c. 6 molecules
d. 24 molecules
e. 38 molecules

15. When an animal cell is metabolizing glucose in the complete absence of molecular oxygen, which one of the following substances is not produced?
a. Acetyl CoA
b. ATP
c. Lactic acid
d. NADH
e. Pyruvic acid