Question 1

Which of the following best describes the difference between catabolic and anabolic reactions in microbial metabolism?

Accepted Answer

Catabolic reactions break down complex molecules to release energy, while anabolic reactions use energy to build complex molecules from simpler ones.

Question 2

Which of the following statements about ATP is CORRECT?

Accepted Answer

ATP is composed of adenine, ribose, and three phosphate groups.

Question 3

What is the main function of enzymes in cellular metabolism?

Accepted Answer

They lower the activation energy required for reactions to proceed.

Question 4

Which of the following is an example of a coenzyme that acts as an electron carrier in redox reactions?

Accepted Answer

Nicotinamide adenine dinucleotide (NAD+)

Question 5

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Competing with the substrate for the active site.

Question 6

Which of the following equations correctly represents 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 7

Which of the following best explains why high temperatures can reduce enzyme activity?

Accepted Answer

High temperatures cause denaturation, disrupting the enzyme's three-dimensional structure.

Question 8

Which process is responsible for the direct transfer of a phosphate group from a high-energy intermediate to ADP to form ATP?

Accepted Answer

Substrate-level phosphorylation

Question 9

During glycolysis, what are the net products generated from one molecule of glucose?

Accepted Answer

2 ATP, 2 NADH, and 2 pyruvic acid

Question 10

Which of the following statements about fermentation is TRUE?

Accepted Answer

Fermentation regenerates NAD+ so glycolysis can continue in the absence of a respiratory chain.

Question 11

Which of the following is a distinguishing feature of the electron transport chain in prokaryotes compared to eukaryotes?

Accepted Answer

Prokaryotes use the plasma membrane for their electron transport chain.

Question 12

Which of the following best describes an amphibolic pathway?

Accepted Answer

A pathway that simultaneously functions in both catabolism and anabolism.

Question 13

Which of the following is NOT a final electron acceptor in anaerobic respiration?

Accepted Answer

Oxygen ($$\mathrm{O_2$})$$

Question 14

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 and able to release more energy upon oxidation.

Question 15

Which of the following is a correct pairing of enzyme class and reaction type?

Accepted Answer

Transferase – transfer of functional groups between molecules

Question 16

Which of the following statements about feedback inhibition is CORRECT?

Accepted Answer

Feedback inhibition slows down or turns off metabolic pathways when end products accumulate.

Question 17

Which of the following best describes the role of ATP synthase in chemiosmosis?

Accepted Answer

It captures the energy of flowing protons to recharge ADP to ATP.

Question 18

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

Accepted Answer

To ensure that metabolic pathways only occur as needed and to maintain balance between anabolism and catabolism.

Question 19

Which of the following statements about autotrophs and heterotrophs is TRUE?

Accepted Answer

Autotrophs make their own organic carbon molecules from inorganic sources via carbon fixation.

Microbial Metabolism: Structure, Function, and Clinical Relevance

Study Guide - Practice Questions