$$\text{ADP} + \text{P}_i \rightarrow \text{ATP}$$

$$\text{NADH} + H^+ + \frac{1}{2} \text{O}_2 \rightarrow \text{NAD}^+ + \text{H}_2\text{O}$$

Question 1

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

Accepted Answer

Catabolism breaks down complex molecules to release energy, which is then used by anabolism to build macromolecules.

Question 2

During glycolysis, glucose is split into two molecules of pyruvic acid. What is the net gain of ATP and NADH from one molecule of glucose?

Accepted Answer

Two ATP and two NADH

Question 3

Which equation correctly represents substrate-level phosphorylation?

Accepted Answer

$$	ext{ADP} + 	ext{P}_i ightarrow 	ext{ATP}$$

Question 4

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

Accepted Answer

Being consumed during the reaction

Question 5

Apoenzymes require which of the following to become active holoenzymes?

Accepted Answer

Inorganic cofactors or coenzymes

Question 6

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

Accepted Answer

It carries electrons from catabolic reactions to the electron transport chain.

Question 7

Which process is responsible for the largest production of ATP during cellular respiration?

Accepted Answer

Electron transport chain and chemiosmosis

Question 8

In the electron transport chain, what is the primary purpose of pumping protons (H+) across the membrane?

Accepted Answer

To create a proton gradient that drives ATP synthesis via ATP synthase

Question 9

Which of the following is a correct equation for the oxidation of NADH in the electron transport chain?

Accepted Answer

$$	ext{NADH} + H^+ + \frac{1}{2} 	ext{O}_2 ightarrow 	ext{NAD}^+ + 	ext{H}_2	ext{O}$$

Question 10

Which of the following is a major difference between aerobic and anaerobic respiration?

Accepted Answer

Aerobic respiration uses oxygen as the final electron acceptor, while anaerobic respiration uses a molecule other than oxygen.

Question 11

Which pathway provides cells with an alternate source of NAD+ when oxygen is not available?

Accepted Answer

Fermentation

Question 12

Which of the following is a product of the Krebs cycle per molecule of glucose?

Accepted Answer

Four molecules of CO2

Question 13

Which of the following best describes the Calvin-Benson cycle?

Accepted Answer

It fixes carbon dioxide into organic molecules using ATP and NADPH.

Question 14

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

Accepted Answer

Transferases

Question 15

Which of the following factors does NOT directly affect the rate of enzymatic reactions?

Accepted Answer

Presence of ribosomes

Question 16

Feedback inhibition in metabolic pathways is best described as:

Accepted Answer

The end product of a pathway inhibits an enzyme early in the pathway.

Question 17

Which of the following is a real-world example of fermentation?

Accepted Answer

Production of ethanol in wine and beer by Saccharomyces

Question 18

Which pathway is amphibolic, meaning it can proceed in both directions depending on cellular needs?

Accepted Answer

Krebs cycle

Question 19

Which of the following is a correct equation for the light-dependent reaction of photosynthesis?

Accepted Answer

$$	ext{ADP} + 	ext{P}_i + 	ext{NADP}^+ + 	ext{H}_2	ext{O} + 	ext{light} ightarrow 	ext{ATP} + 	ext{NADPH} + 	ext{O}_2$$

Microbial Metabolism: Key Concepts and Pathways

Study Guide - Practice Questions