Question 1

Which of the following best describes the difference between catabolism and anabolism in cellular metabolism?

Accepted Answer

Catabolism breaks down molecules to release energy, while anabolism synthesizes cellular materials using energy.

Question 2

Which of the following reactions is considered exergonic?

Accepted Answer

The hydrolysis of ATP to ADP and P$$_i$$

Question 3

In the context of redox reactions, what does it mean if a molecule has a highly negative reduction potential ($$E_0$$'$$)?

Accepted Answer

It is a strong electron donor.

Question 4

Which of the following best explains why enzymes are considered biological catalysts?

Accepted Answer

They lower the activation energy and are not altered by the reaction.

Question 5

Which enzyme class is responsible for transferring functional groups between molecules?

Accepted Answer

Transferases

Question 6

Refer to the redox tower. Why does the oxidation of glucose by O$$_2$$ yield more free energy than by NO$$_3^-$$?

Accepted Answer

O$$_2$$ has a higher (more positive) reduction potential than NO$$_3^-.$$

Question 7

Which of the following is a coenzyme involved in redox reactions during metabolism?

Accepted Answer

NAD$$^+$$

Question 8

During glycolysis, what is the net gain of ATP and NADH per molecule of glucose?

Accepted Answer

$$2$$ ATP and $$2$$ NADH

Question 9

Which process allows cells to regenerate NAD$$^+ in $$the absence of oxygen, enabling glycolysis to continue?

Accepted Answer

Fermentation

Question 10

Which of the following is a product of homolactic fermentation?

Accepted Answer

Lactic acid

Question 11

What is the main function of the electron transport chain in prokaryotes?

Accepted Answer

To generate a proton motive force across the membrane

Question 12

Which of the following best describes substrate-level phosphorylation?

Accepted Answer

ATP synthesis by direct transfer of a phosphate group from a substrate to ADP

Question 13

Which enzyme catalyzes the conversion of glucose to glucose-6-phosphate in glycolysis?

Accepted Answer

Hexokinase

Question 14

Which of the following is NOT a function of the citric acid cycle?

Accepted Answer

Direct regeneration of NAD$$^+$$ from NADH

Question 15

Which of the following statements about fermentation is TRUE?

Accepted Answer

Fermentation regenerates NAD$$^+ to $$allow glycolysis to continue.

Question 16

Which enzyme class catalyzes the rearrangement of atoms within a molecule?

Accepted Answer

Isomerases

Question 17

Which of the following is a real-world application of microbial fermentation?

Accepted Answer

Production of lactic acid for yogurt

Question 18

What is the role of ATP synthase in cellular respiration?

Accepted Answer

It uses the proton motive force to synthesize ATP from ADP and P$$_i.$$

Question 19

Which of the following best describes the fate of pyruvate in the presence of oxygen?

Accepted Answer

It is completely oxidized to CO$$_2$$ via the citric acid cycle.

Question 20

Which of the following statements about enzyme cofactors is CORRECT?

Accepted Answer

Coenzymes are often derived from vitamins and are loosely bound to enzymes.

Microbial Metabolism and Energetics: An Overview

Study Guide - Practice Questions