Question 1

Which statement best describes the difference between a closed system and its surroundings in the context of thermodynamics?

Accepted Answer

A closed system can exchange energy but not matter with its surroundings.

Question 2

Which of the following is an example of potential energy in biological systems?

Accepted Answer

The chemical bonds in glucose molecules.

Question 3

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

Accepted Answer

Energy can be transferred from one form to another, but cannot be destroyed.

Question 4

Which equation correctly represents the chemical reaction for aerobic cellular respiration?

Accepted Answer

$$\mathrm{Glucose} + \mathrm{O}_2 \rightarrow \mathrm{CO}_2 + \mathrm{H}_2O + \mathrm{ATP}$$

Question 5

Which process is responsible for the transfer of a phosphate group from ATP to another molecule?

Accepted Answer

Phosphorylation

Question 6

During glycolysis, which type of phosphorylation is responsible for ATP production?

Accepted Answer

Substrate-level phosphorylation

Question 7

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

Accepted Answer

NADH carries electrons to the electron transport chain, where they are used to produce ATP.

Question 8

Which of the following is true about exergonic reactions?

Accepted Answer

They release energy, and the products have lower energy than the reactants.

Question 9

What is the main function of enzymes in biological systems?

Accepted Answer

To lower the activation energy and speed up chemical reactions.

Question 10

Which of the following best describes competitive inhibition of an enzyme?

Accepted Answer

An inhibitor competes with the substrate for binding at the active site.

Question 11

Which statement about feedback inhibition is correct?

Accepted Answer

The final product of a pathway inhibits an earlier step, stopping further production.

Question 12

Which of the following is true about oxidation-reduction (redox) reactions?

Accepted Answer

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

Question 13

Which of the following is NOT a function of cofactors in enzyme activity?

Accepted Answer

Being consumed in the reaction as reactants.

Question 14

Which of the following statements about substrate-level phosphorylation is correct?

Accepted Answer

It directly transfers a phosphate group from a substrate to ADP to form ATP.

Question 15

During aerobic cellular respiration, what is the final electron acceptor in the electron transport chain?

Accepted Answer

Oxygen ($$\mathrm{O}_2)$$

Question 16

Which process produces the most ATP during aerobic cellular respiration?

Accepted Answer

Oxidative phosphorylation

Question 17

Which of the following is a correct description of chemiosmosis?

Accepted Answer

Diffusion of ions across a membrane down their concentration gradient, driving ATP synthesis.

Question 18

Which of the following is true about the second law of thermodynamics in biological systems?

Accepted Answer

Energy transfer is always accompanied by an increase in entropy.

Question 19

Which of the following is a product of the electron transport chain in aerobic respiration?

Accepted Answer

Water ($$\mathrm{H}_2O)$$

Question 20

Which statement best explains why enzymes are specific to their substrates?

Accepted Answer

Enzymes have active sites that are shaped to fit only specific substrates.

Microbial Metabolism: Thermodynamics, Enzymes, and Cellular Respiration

Study Guide - Practice Questions