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.

Question 2

According to collision theory, which factor does NOT increase the reaction rate of an enzyme-catalyzed reaction?

Accepted Answer

Decreasing enzyme concentration

Question 3

What is the role of a coenzyme in enzymatic reactions?

Accepted Answer

It is an organic cofactor that assists enzymes, often by acting as an electron carrier.

Question 4

Which enzyme type is responsible for catalyzing the rearrangement of atoms within a molecule?

Accepted Answer

Isomerase

Question 5

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Filling the active site and competing with the substrate for binding.

Question 6

Which of the following is TRUE about feedback inhibition?

Accepted Answer

The end-product of a pathway allosterically inhibits an enzyme from earlier in the pathway.

Question 7

Which of the following equations correctly represents the overall reaction for aerobic respiration in prokaryotes?

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

During oxidative phosphorylation, ATP is generated by:

Accepted Answer

Using energy released from electrons transferred along an electron transport chain to power ATP synthase.

Question 9

Which statement about fermentation is correct?

Accepted Answer

Fermentation uses an organic molecule as the final electron acceptor and produces small amounts of ATP.

Question 10

Which of the following is a product of lactic acid fermentation?

Accepted Answer

Lactic acid only

Question 11

What is the main difference between oxygenic and anoxygenic photosynthesis?

Accepted Answer

Oxygenic photosynthesis produces $$O_2 as a $$byproduct, while anoxygenic photosynthesis does not.

Question 12

Which metabolic pathway is responsible for the oxidation of glucose to pyruvic acid, producing ATP and NADH?

Accepted Answer

Glycolysis

Question 13

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

Accepted Answer

It uses oxygen as the final electron acceptor.

Question 14

Which of the following is NOT a factor that influences enzyme activity?

Accepted Answer

Presence of ribosomes

Question 15

Which of the following is a correct description of substrate-level phosphorylation?

Accepted Answer

ATP is generated when a high-energy phosphate group is directly transferred from a substrate to ADP.

Question 16

Which coenzyme is commonly involved in redox reactions as an electron carrier in metabolism?

Accepted Answer

Nicotinamide adenine dinucleotide (NAD$$^+)$$

Question 17

A bacterium is found to use nitrate ($$NO_3$$^-$$) as its final electron acceptor in respiration. What type of respiration is this?

Accepted Answer

Anaerobic respiration

Question 18

Which metabolic pathway provides intermediates for synthesis reactions and operates simultaneously with glycolysis?

Accepted Answer

Pentose phosphate pathway

Question 19

Which of the following is TRUE about ribozymes?

Accepted Answer

They are RNA molecules that function as catalysts and are not used up in the reaction.

Question 20

Which of the following best describes an amphibolic pathway?

Accepted Answer

A pathway that functions in both anabolism and catabolism.

Microbial Metabolism: Structured Study Notes for Microbiology Students

Study Guide - Practice Questions