$$C_6H_{12}O_6$ + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{ATP}$$

Question 1

Which of the following statements best describes the role of ATP hydrolysis in cellular metabolism?

Accepted Answer

ATP hydrolysis releases energy that can be used to drive endergonic reactions by coupling them to exergonic ATP breakdown.

Question 2

A reaction has a change in free energy $$\Delta G = -7.3$$ kcal/mol. What does this indicate about the reaction?

Accepted Answer

The reaction is exergonic and will proceed spontaneously.

Question 3

Which of the following best explains why enzymes are necessary for biological reactions?

Accepted Answer

Enzymes lower the activation energy required for reactions, allowing them to occur rapidly at cellular temperatures.

Question 4

Which of the following is an example of feedback inhibition in metabolic pathways?

Accepted Answer

The end product of a pathway binds to an enzyme involved earlier in the pathway, inhibiting its activity.

Question 5

According to the second law of thermodynamics, what happens to the entropy of the universe during any energy transformation?

Accepted Answer

The entropy of the universe increases.

Question 6

Which equation correctly represents the Gibbs free energy change for a reaction?

Accepted Answer

$$\Delta G = \Delta H - T \Delta S$$

Question 7

A cell is performing aerobic respiration. Which of the following is the correct general equation for this process?

Accepted Answer

$$C_6H_{12}O_6$ + 6O_2 ightarrow 6CO_2 + 6H_2O + 	ext{ATP}$$

Question 8

Which of the following best describes an anabolic pathway?

Accepted Answer

A pathway that combines simple molecules to form complex molecules, requiring energy input.

Question 9

Which of the following reactions is most likely to be spontaneous under standard conditions?

Accepted Answer

A reaction with $$\Delta G \u003c 0$$

Question 10

In cellular respiration, which process produces the most ATP per glucose molecule?

Accepted Answer

Aerobic respiration

Question 11

Which of the following statements about endergonic and exergonic reactions is correct?

Accepted Answer

Endergonic reactions absorb energy and are non-spontaneous.

Question 12

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 13

Which of the following best describes energy coupling in cells?

Accepted Answer

Using the energy released from an exergonic reaction to drive an endergonic reaction.

Question 14

Which of the following is NOT a factor that affects enzyme activity?

Accepted Answer

The color of the enzyme

Question 15

Which statement about metabolic pathways is correct?

Accepted Answer

Catabolic pathways break down complex molecules into simpler ones, releasing energy.

Question 16

If a cell's metabolic pathway is regulated by allosteric inhibition, what is happening?

Accepted Answer

A molecule binds to a site other than the active site, changing the enzyme's shape and reducing its activity.

Question 17

Which of the following is a correct example of energy transformation in biological systems?

Accepted Answer

Conversion of chemical energy in glucose to ATP during cellular respiration.

Question 18

Which of the following best describes the difference between open and closed systems in thermodynamics as applied to biology?

Accepted Answer

Open systems exchange both energy and matter with their surroundings, while closed systems exchange only energy.

Question 19

Which of the following is true about spontaneous reactions in biological systems?

Accepted Answer

They have a negative change in free energy ($$\Delta G \u003c 0).$$

Energy, Metabolism, and Enzyme Function in Biological Systems

Guida di studio - Domande di pratica