Question 1

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

Accepted Answer

Enzymes act as organic catalysts that lower the activation energy, speeding up reactions.

Question 2

During glycolysis, what are the net products generated from one molecule of glucose?

Accepted Answer

2 pyruvate, 2 ATP, and 2 NADH

Question 3

Which equation correctly represents the overall process of photosynthesis?

Accepted Answer

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

Question 4

Which of the following statements about competitive inhibition is correct?

Accepted Answer

The inhibitor binds to the active site, preventing the substrate from binding.

Question 5

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

Accepted Answer

Oxidative phosphorylation

Question 6

Which of the following is true regarding the energy changes in exergonic and endergonic reactions?

Accepted Answer

Exergonic reactions release energy, while endergonic reactions require energy input.

Question 7

Which of the following factors does NOT affect enzyme activity?

Accepted Answer

The color of the substrate

Question 8

If a cell is placed in an environment with a noncompetitive inhibitor, what is the most likely effect on enzyme activity?

Accepted Answer

The inhibitor binds elsewhere on the enzyme, changing its shape and reducing activity.

Question 9

Which molecule acts as the final electron acceptor in the electron transport chain during aerobic respiration?

Accepted Answer

O$$_2$$

Question 10

A mutation causes an enzyme's active site to change shape. What is the most likely consequence?

Accepted Answer

The enzyme will no longer bind its substrate effectively.

Question 11

Which of the following is a direct product of the light-dependent reactions of photosynthesis?

Accepted Answer

ATP and NADPH

Question 12

Which step in glycolysis is responsible for the net production of ATP?

Accepted Answer

Conversion of phosphoenolpyruvate to pyruvate

Question 13

Which of the following best explains why increasing substrate concentration can overcome competitive inhibition but not noncompetitive inhibition?

Accepted Answer

Competitive inhibitors compete with the substrate for the active site, so more substrate can outcompete the inhibitor.

Question 14

Which of the following is the correct sequence of events in aerobic respiration?

Accepted Answer

Glycolysis $$\rightarrow$$ Krebs cycle $$\rightarrow$$ Electron transport chain

Question 15

Which of the following is true about the ATP yield from aerobic respiration compared to anaerobic respiration?

Accepted Answer

Aerobic respiration yields more ATP than anaerobic respiration.

Question 16

A patient is diagnosed with a mitochondrial disorder that impairs oxidative phosphorylation. Which of the following would most likely be observed?

Accepted Answer

Decreased production of ATP

Question 17

Which of the following is a key difference between exergonic and endergonic reactions?

Accepted Answer

Exergonic reactions release energy; endergonic reactions require energy input.

Question 18

Which of the following is the correct formula for the net ATP production from one glucose molecule during aerobic respiration?

Accepted Answer

$$36$$ ATP

Question 19

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

Accepted Answer

Cells use exergonic reactions to drive endergonic reactions.

Question 20

Which of the following is true about the products of the Krebs cycle per glucose molecule?

Accepted Answer

2 ATP, 6 NADH, 2 FADH$$_2$$

Cellular Energetics: Enzymes, Energy, and Glycolysis

Study Guide - Practice Questions