$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{ADP} + \mathrm{P}_i + \text{energy}$$

Question 1

Which of the following best describes the role of metabolic enzymes in cellular metabolism?

Accepted Answer

They are proteins that act as biologic catalysts, accelerating specific chemical reactions.

Question 2

What is the primary difference between catabolic and anabolic reactions?

Accepted Answer

Catabolic reactions break down molecules and release energy, while anabolic reactions build molecules and store energy.

Question 3

Which factor does NOT affect the efficiency of an enzyme?

Accepted Answer

The color of the enzyme

Question 4

Apoenzymes require which of the following to function?

Accepted Answer

A nonprotein cofactor such as Ca$$^{2+}$$, Fe$$^{2+}$$, Mg$$^{2+}$$, or Cu$$^{2+}$$

Question 5

Which statement about exoenzymes is correct?

Accepted Answer

Exoenzymes are released outside the cell to catalyze extracellular reactions.

Question 6

Which of the following is the correct sequence of protein structure levels?

Accepted Answer

Primary, secondary, tertiary

Question 7

During aerobic respiration, which phase occurs first?

Accepted Answer

Glycolysis

Question 8

Which equation correctly represents the hydrolysis of ATP?

Accepted Answer

$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} ightarrow \mathrm{ADP} + \mathrm{P}_i + 	ext{energy}$$

Question 9

Which of the following is a product of the Krebs cycle that is used in the electron transport chain?

Accepted Answer

NADH

Question 10

Why is aerobic respiration considered more efficient than fermentation?

Accepted Answer

Aerobic respiration produces more ATP per molecule of glucose.

Question 11

Which of the following best describes the specificity of enzymes?

Accepted Answer

Each enzyme catalyzes only one particular chemical reaction for a specific substrate.

Question 12

Which of the following is NOT a function that requires energy in a cell?

Accepted Answer

Passive diffusion of water

Question 13

Which pathway is used by cells to catabolize glucose in the absence of oxygen?

Accepted Answer

Fermentation

Question 14

In prokaryotic cells, where do the Krebs cycle and electron transport chain occur?

Accepted Answer

At the inner surface of the cell membrane

Question 15

Which of the following is a plausible consequence of heavy metal inhibitors on enzyme activity?

Accepted Answer

Enzyme efficiency decreases due to disruption of the active site.

Question 16

Which of the following is true about the electron transport chain in aerobic respiration?

Accepted Answer

It produces a large number of ATP molecules by oxidative phosphorylation.

Question 17

Which of the following is a correct statement about ATP?

Accepted Answer

ATP is used to transfer energy from catabolic to anabolic reactions.

Question 18

Which of the following is a multi-step biochemical pathway that requires a specific enzyme for each step?

Accepted Answer

Glycolysis

Question 19

Which of the following is NOT a product of fermentation?

Accepted Answer

Oxygen

Question 20

Which of the following best explains why some energy is lost as heat during catabolic reactions?

Accepted Answer

Not all chemical bond energy is converted to ATP; some is released as heat.

Metabolic Enzymes and Cellular Metabolism in Microbiology

Study Guide - Practice Questions