Q: Which equation correctly represents the change in free energy ($$\Delta G) $$for a chemical reaction?

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

Question 1

Which of the following best describes the difference between potential energy and kinetic energy in biological systems?

Accepted Answer

Potential energy is stored in molecular bonds, while kinetic energy is the energy of movement.

Question 2

According to the first law of thermodynamics, which statement is correct regarding energy in a closed biological system?

Accepted Answer

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

Question 3

A diver standing on a platform has high potential energy. When the diver jumps, what happens to this energy?

Accepted Answer

Potential energy is converted to kinetic energy as the diver falls.

Question 4

Which equation correctly represents the change in free energy ($$\Delta G) $$for a chemical reaction?

Accepted Answer

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

Question 5

An exergonic reaction has a $$\Delta G of -5.6 $$kcal/mol. Which of the following statements is most accurate?

Accepted Answer

The reaction releases energy and can occur spontaneously.

Question 6

ATP hydrolysis is often used to drive endergonic reactions in cells. What is the $$\Delta G$$ for ATP hydrolysis under standard conditions?

Accepted Answer

$$\Delta G \approx -7.3$$ kcal/mol

Question 7

Which of the following best explains why enzymes speed up chemical reactions?

Accepted Answer

Enzymes lower the activation energy ($$E_a) $$required for the reaction to proceed.

Question 8

A mutation causes an enzyme to lose its tertiary structure. What is the most likely consequence?

Accepted Answer

The enzyme will lose its active site and become nonfunctional.

Question 9

Which of the following scenarios illustrates allosteric inhibition of an enzyme?

Accepted Answer

A regulatory molecule binds to a site other than the active site, changing the enzyme's shape and preventing substrate binding.

Question 10

Which of the following is true about the coupling of exergonic and endergonic reactions in metabolism?

Accepted Answer

Energy released from exergonic reactions is used to drive endergonic reactions.

Question 11

A patient has a genetic disorder that causes their enzymes to function only at a pH of 5. What is the most likely effect if their blood pH rises to 7.4?

Accepted Answer

The enzymes will lose activity due to denaturation or improper folding.

Question 12

Which of the following is a correct statement about the second law of thermodynamics in biological systems?

Accepted Answer

Every energy transformation increases the disorder (entropy) of the universe.

Question 13

During aerobic metabolism, which molecule acts as the final electron acceptor?

Accepted Answer

O$$_2$$

Question 14

Which of the following best describes the role of the active site in enzyme function?

Accepted Answer

It is the region where substrates bind and the reaction is catalyzed.

Question 15

A metabolic pathway is regulated by feedback inhibition. Which statement best describes this process?

Accepted Answer

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

Question 16

Which of the following is a real-world example of energy transformation in living organisms?

Accepted Answer

Muscle contraction converts chemical energy from ATP into kinetic energy.

Question 17

If a reaction has a positive $$\Delta G$$, which of the following is true?

Accepted Answer

The reaction is endergonic and requires energy input to proceed.

Question 18

Which of the following statements about enzyme specificity is correct?

Accepted Answer

Enzymes are highly specific and typically catalyze only one type of reaction.

Question 19

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Energy, Enzymes, and Introduction to Metabolism: Study Notes for General Biology

Study Guide - Practice Questions

Study Guide - Flashcards