Question 1

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

Accepted Answer

Anabolism involves dehydration synthesis to build polymers, while catabolism involves hydrolysis to break down polymers.

Question 2

According to the first law of thermodynamics, which of the following statements is correct?

Accepted Answer

Energy can be transformed from one form to another, but the total amount remains constant.

Question 3

A reaction has a Gibbs free energy change of $$\Delta G = -5.0$$ kcal/mol. Which of the following is true about this reaction?

Accepted Answer

The reaction is exergonic and will proceed spontaneously.

Question 4

Which of the following best explains why ATP is considered the 'universal energy currency' in cells?

Accepted Answer

ATP hydrolysis releases just enough energy for most cellular reactions and is easily regenerated.

Question 5

Which of the following is an example of substrate-level phosphorylation?

Accepted Answer

ATP synthesis during glycolysis by direct transfer of a phosphate group from phosphoenolpyruvate to ADP.

Question 6

Which of the following statements about enzymes is FALSE?

Accepted Answer

Enzymes are consumed during the reaction.

Question 7

A competitive inhibitor of an enzyme acts by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 8

Which of the following best describes feedback inhibition in a metabolic pathway?

Accepted Answer

The end-product of the pathway acts as an allosteric inhibitor of an early enzyme in the pathway.

Question 9

Which of the following is a correct statement about redox reactions in microbial metabolism?

Accepted Answer

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

Question 10

Which of the following best explains why living systems require a constant input of energy?

Accepted Answer

Living systems are highly ordered and must counteract the increase in entropy dictated by the second law of thermodynamics.

Question 11

Which of the following is true about the effect of temperature on enzyme activity?

Accepted Answer

Enzyme activity is optimal at a certain temperature, but too much heat can denature the enzyme.

Question 12

A patient is diagnosed with a metabolic disorder where their cells cannot efficiently regenerate NAD+. Which process would be most directly affected?

Accepted Answer

Glycolysis

Question 13

Which of the following best describes the role of coenzymes in enzyme function?

Accepted Answer

Coenzymes are organic molecules that assist enzymes by carrying chemical groups or electrons.

Question 14

Which of the following equations correctly represents the calculation of Gibbs free energy change for a reaction?

Accepted Answer

$$\Delta G = G_{products} - G_{reactants}$$

Question 15

Which of the following is a real-life example of an exergonic reaction in cells?

Accepted Answer

Hydrolysis of ATP to ADP and inorganic phosphate

Question 16

A scientist adds a molecule that binds to an enzyme's allosteric site and increases its activity. This is an example of:

Accepted Answer

Allosteric activation

Question 17

Which of the following best describes the relationship between catabolic and anabolic pathways in cells?

Accepted Answer

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

Question 18

Which of the following is NOT a function of enzymes in biological systems?

Accepted Answer

Changing the equilibrium position of a reaction

Question 19

Which of the following statements about energy coupling in cells is correct?

Accepted Answer

Endergonic reactions are driven by coupling them to exergonic reactions such as ATP hydrolysis.

Microbial Metabolism: Foundations and Mechanisms

Study Guide - Practice Questions