Question 1

Which of the following best describes metabolism in a microbial cell?

Accepted Answer

The sum of all chemical reactions that lead to the energy exchanges required for growth and reproduction.

Question 2

Cells require energy for various functions. Which of the following is NOT a direct use of energy in microbial cells?

Accepted Answer

Passive diffusion of water

Question 3

Microbes harvest energy from organic and inorganic substrates. Which molecule is the primary energy currency in cells?

Accepted Answer

Adenosine triphosphate (ATP)

Question 4

Which of the following best explains why ATP is considered the 'energy currency' of the cell?

Accepted Answer

ATP stores energy in its high-energy phosphate bonds, which can be broken to release energy for cellular work.

Question 5

Catabolic and anabolic reactions are coupled in cells. Which statement best describes this relationship?

Accepted Answer

Catabolic reactions release energy that is used to drive anabolic reactions.

Question 6

Which of the following is true regarding redox (reduction-oxidation) reactions in microbial metabolism?

Accepted Answer

Redox reactions involve the transfer of electrons from one molecule to another and are always coupled.

Question 7

Which of the following molecules acts as a primary electron carrier in cellular metabolism and is derived from B vitamins?

Accepted Answer

NAD+ (nicotinamide adenine dinucleotide)

Question 8

A patient is given a drug that inhibits the function of NAD+. What is the most likely effect on the patient's cells?

Accepted Answer

The cells will be unable to efficiently transfer electrons during metabolism, leading to decreased ATP production.

Question 9

Which of the following best describes the role of enzymes in metabolic reactions?

Accepted Answer

Enzymes lower the activation energy required for a chemical reaction to occur.

Question 10

Which factor does NOT directly influence the rate of enzymatic reactions?

Accepted Answer

The color of the enzyme

Question 11

A competitive inhibitor affects an enzyme by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 12

Which of the following statements about protein structure is correct?

Accepted Answer

The primary structure of a protein is the unique sequence of amino acids.

Question 13

During glycolysis (EMP pathway), what is the net gain of ATP molecules per molecule of glucose?

Accepted Answer

$2$

Question 14

Which of the following is a correct summary of the overall reaction for glycolysis?

Accepted Answer

$\mathrm{Glucose} + 2\ \mathrm{NAD}^+ + 2\ \mathrm{ADP} + 2\ \mathrm{P_i} \rightarrow 2\ \mathrm{Pyruvate} + 2\ \mathrm{NADH} + 2\ \mathrm{ATP} + 2\ \mathrm{H_2O}$

Question 15

In the context of carbohydrate catabolism, which pathway is responsible for the initial breakdown of glucose to pyruvate?

Accepted Answer

Embden-Meyerhof-Parnas (EMP) pathway

Question 16

A mutation in a bacterium prevents the formation of the enzyme hexokinase. What is the most likely effect on glycolysis?

Accepted Answer

Glycolysis will be inhibited because glucose cannot be phosphorylated to glucose-6-phosphate.

Question 17

Which of the following best describes substrate-level phosphorylation?

Accepted Answer

The direct transfer of a phosphate group from a substrate to ADP to form ATP.

Question 18

During aerobic respiration, what is the fate of pyruvate produced by glycolysis?

Accepted Answer

It is oxidized to acetyl-CoA, which enters the citric acid cycle.

Question 19

Which of the following statements about the pentose phosphate pathway is correct?

Accepted Answer

It generates NADPH and ribose-5-phosphate for biosynthetic reactions.

Question 20

A scientist is studying a new bacterial species that lacks the ability to perform oxidative phosphorylation. Which of the following is most likely true about this organism?

Accepted Answer

It relies primarily on substrate-level phosphorylation for ATP production.

Microbial Metabolism: Study Notes for MIC 205

Study Guide - Practice Questions

Study Guide - Flashcards