$$ \mathrm{ATP} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{ADP} + \mathrm{P}_i + \text{energy} $$

Question 1

Which of the following best describes an amphibolic pathway in microbial metabolism?

Accepted Answer

A pathway that can function in both catabolism and anabolism.

Question 2

What is the primary role of ATP in cellular metabolism?

Accepted Answer

To provide energy for cellular work and anabolic reactions.

Question 3

Which of the following equations correctly represents the dephosphorylation of ATP?

Accepted Answer

$$ \mathrm{ATP} + \mathrm{H}_2\mathrm{O} ightarrow \mathrm{ADP} + \mathrm{P}_i + 	ext{energy} $$

Question 4

A competitive inhibitor of an enzyme acts by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 5

Which of the following statements about redox reactions is correct?

Accepted Answer

Oxidation is the loss of electrons, and reduction is the gain of electrons.

Question 6

In the reaction $$ \mathrm{Fe} + \mathrm{Cu}^{2+} \rightarrow \mathrm{Fe}^{2+} + \mathrm{Cu} $$, which element is oxidized?

Accepted Answer

Fe

Question 7

Which of the following best describes substrate-level phosphorylation?

Accepted Answer

ATP is produced directly by transferring a phosphate group from a high-energy substrate to ADP.

Question 8

Where does the Krebs cycle occur in eukaryotic cells?

Accepted Answer

Mitochondrial matrix

Question 9

Which of the following is a key difference between fermentation and anaerobic respiration?

Accepted Answer

Fermentation does not use an electron transport chain, while anaerobic respiration does.

Question 10

A bacterial culture produces a black precipitate in a medium containing iron. What metabolic process is indicated?

Accepted Answer

Sulfur reduction with H$$_2S $$production

Question 11

Which test would you use to detect the presence of cytochrome c oxidase in a bacterial isolate?

Accepted Answer

Oxidase test

Question 12

A positive catalase test is indicated by:

Accepted Answer

The production of bubbles when hydrogen peroxide is added

Question 13

Which of the following best explains why cells must regenerate NAD$$^+$$ during fermentation?

Accepted Answer

To allow glycolysis to continue producing ATP in the absence of an electron transport chain.

Question 14

Which fermentation pathway is detected by the Voges-Proskauer (VP) test?

Accepted Answer

Butanediol fermentation

Question 15

A bacterial isolate is positive for the methyl red (MR) test. What does this indicate?

Accepted Answer

The bacterium performs mixed-acid fermentation.

Question 16

Which of the following best describes the role of NADH in cellular respiration?

Accepted Answer

It donates electrons to the electron transport chain.

Question 17

Which of the following steps in cellular respiration occurs in the cytoplasm of both prokaryotes and eukaryotes?

Accepted Answer

Glycolysis

Question 18

A patient sample is tested using the API system. What is the main advantage of this system in clinical microbiology?

Accepted Answer

It provides a rapid, standardized metabolic profile for bacterial identification.

Question 19

Which of the following is a correct summary equation for aerobic cellular respiration?

Accepted Answer

$$ \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2 ightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2\mathrm{O} + 	ext{energy} $$

Question 20

Which of the following best describes feedback inhibition in metabolic pathways?

Accepted Answer

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

Microbial Metabolism: Structured Study Guide

Study Guide - Practice Questions