Question 1

Which of the following best describes an amphibolic pathway?

Accepted Answer

A pathway that can function in both catabolism and anabolism, depending on cellular needs.

Question 2

Which of the following statements about ATP is FALSE?

Accepted Answer

ATP is primarily produced by anabolic reactions.

Question 3

A scientist is studying an enzyme that requires magnesium ions to function. What is the enzyme called when the magnesium ion is NOT bound?

Accepted Answer

Apoenzyme

Question 4

Which of the following is an example of substrate-level phosphorylation?

Accepted Answer

ATP synthesis during glycolysis

Question 5

Which of the following best explains why high fever can be dangerous for humans at the molecular level?

Accepted Answer

High temperatures can denature enzymes, disrupting their three-dimensional structure and decreasing their activity.

Question 6

Which of the following is TRUE regarding the difference between competitive and noncompetitive enzyme inhibition?

Accepted Answer

Competitive inhibitors can be overcome by increasing substrate concentration, while noncompetitive inhibitors cannot.

Question 7

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 8

A patient with diabetic ketoacidosis has a low blood pH. Why is this condition potentially deadly?

Accepted Answer

Low pH can denature proteins, including enzymes, disrupting cellular function.

Question 9

Which of the following best describes the role of NAD+ in cellular respiration?

Accepted Answer

It acts as an electron carrier, accepting electrons during glycolysis and the Krebs cycle.

Question 10

Which of the following is NOT a characteristic of enzymes?

Accepted Answer

They are consumed during the reaction.

Question 11

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 12

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

Accepted Answer

Transferase – transfer of functional groups between molecules

Question 13

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

Accepted Answer

Fats contain more C-H bonds, making them more reduced and able to release more energy upon oxidation.

Question 14

Which of the following is a likely result if a bacterium lacks cytochrome c oxidase?

Accepted Answer

It will be unable to use oxygen as a final electron acceptor in aerobic respiration.

Question 15

Which of the following best describes the effect of increasing substrate concentration on enzyme activity when the enzyme concentration is constant?

Accepted Answer

The reaction rate will increase until all enzyme active sites are saturated, then level off.

Question 16

Which of the following is a function of feedback inhibition in metabolic pathways?

Accepted Answer

To slow down or stop a pathway when enough end product has accumulated.

Question 17

Which of the following is TRUE about the pentose phosphate pathway?

Accepted Answer

It produces NADPH and pentoses that can be used for nucleotide synthesis.

Question 18

Which of the following best describes the role of ATP synthase in oxidative phosphorylation?

Accepted Answer

It uses the proton motive force to synthesize ATP from ADP and inorganic phosphate.

Question 19

Which of the following is NOT a product of mixed acid fermentation?

Accepted Answer

Acetyl-CoA

Microbial Metabolism: Structure, Function, and Clinical Relevance

Study Guide - Practice Questions