Question 1

Which of the following best describes an amphibolic pathway?

Accepted Answer

A pathway that can function in both catabolism and anabolism.

Question 2

Which of the following is TRUE regarding ATP in cellular metabolism?

Accepted Answer

ATP is continuously recycled from ADP through phosphorylation and dephosphorylation.

Question 3

Which of the following statements about enzymes is CORRECT?

Accepted Answer

Enzymes are specific protein catalysts that lower the activation energy of reactions.

Question 4

A competitive inhibitor of an enzyme acts by:

Accepted Answer

Binding to the active site, preventing substrate binding.

Question 5

Which coenzyme is commonly used as an electron carrier in catabolic reactions?

Accepted Answer

NAD+

Question 6

What is the main purpose of fermentation in microbial metabolism?

Accepted Answer

To regenerate NAD+ so glycolysis can continue.

Question 7

Which of the following is a product of the intermediate step between glycolysis and the Krebs cycle?

Accepted Answer

Acetyl-CoA

Question 8

Which process directly produces ATP by transferring a phosphate group from a high-energy intermediate to ADP?

Accepted Answer

Substrate-level phosphorylation

Question 9

In aerobic respiration, what is the final electron acceptor in the electron transport chain?

Accepted Answer

Oxygen (O2)

Question 10

Which of the following best explains why fats yield more ATP than carbohydrates when oxidized?

Accepted Answer

Fats contain more hydrocarbon bonds, making them more reduced.

Question 11

Which of the following is NOT a function of coenzymes in metabolism?

Accepted Answer

Providing structural support to enzymes.

Question 12

A bacterial species is found to be oxidase negative. What does this indicate about its electron transport chain?

Accepted Answer

It lacks cytochrome c oxidase in its electron transport chain.

Question 13

Which of the following is a correct summary of the overall reaction for aerobic respiration?

Accepted Answer

$$\mathrm{C_6H_{12}O_6$} + 6\mathrm{O_2$} + 38\mathrm{ADP} + 38\mathrm{P_i} \rightarrow 6\mathrm{CO_2$} + 6\mathrm{H_2O} + 38\mathrm{ATP}$$

Question 14

Which of the following best describes the role of ATP synthase in cellular respiration?

Accepted Answer

It captures the energy of flowing protons to synthesize ATP from ADP and Pi.

Question 15

Which of the following is a distinguishing feature of fermentation compared to aerobic and anaerobic respiration?

Accepted Answer

Fermentation uses an organic molecule as the final electron acceptor.

Question 16

Which of the following is a correct pairing of a metabolic test and what it detects?

Accepted Answer

Oxidase test – detects the presence of cytochrome c oxidase.

Question 17

Which of the following statements about anabolic pathways is TRUE?

Accepted Answer

They require ATP and reducing power to build complex molecules.

Question 18

Which of the following is a reason why cells regulate enzyme activity?

Accepted Answer

To conserve energy and resources by turning off pathways when products are sufficient.

Question 19

Which of the following best describes a chemoheterotroph?

Accepted Answer

An organism that uses chemical compounds for energy and organic compounds for carbon.

Microbial Metabolism: Foundations, Pathways, and Regulation

Study Guide - Practice Questions