Question 1

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

Accepted Answer

Enzymes lower the activation energy, allowing reactions to proceed more rapidly.

Question 2

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

Accepted Answer

2 pyruvate, 2 ATP, 2 NADH

Question 3

Which of the following statements about aerobic and anaerobic respiration is correct?

Accepted Answer

Aerobic respiration results in the complete oxidation of glucose to $$CO_2$$ and $$H_2O.$$

Question 4

Which of the following best explains why enzymes are specific to their substrates?

Accepted Answer

The active site of an enzyme has a unique shape that only fits specific substrates.

Question 5

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Binding to the active site, preventing substrate binding.

Question 6

Which of the following equations correctly represents the overall process of photosynthesis?

Accepted Answer

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

Question 7

In the context of cellular energetics, what is the main difference between exergonic and endergonic reactions?

Accepted Answer

Exergonic reactions release energy ($$\Delta G  0).$$

Question 8

Which of the following is true regarding the light-dependent reactions of photosynthesis?

Accepted Answer

They produce ATP and NADPH, which are used in the Calvin cycle.

Question 9

A patient is diagnosed with a genetic disorder that results in nonfunctional ATP synthase. Which process would be most directly affected?

Accepted Answer

Electron transport chain oxidative phosphorylation

Question 10

Which of the following best describes substrate-level phosphorylation?

Accepted Answer

ATP is produced directly by transferring a phosphate group from a substrate to ADP.

Question 11

Which of the following factors does NOT affect enzyme activity?

Accepted Answer

The atomic number of the enzyme

Question 12

During the process of glycolysis, which molecule acts as an electron carrier?

Accepted Answer

NAD+

Question 13

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

Accepted Answer

Cells couple exergonic reactions, such as ATP hydrolysis, to drive endergonic reactions.

Question 14

A noncompetitive inhibitor affects enzyme activity by:

Accepted Answer

Binding to a site other than the active site, changing the enzyme's shape.

Question 15

Which of the following is a correct statement about the energy yield of aerobic respiration?

Accepted Answer

Aerobic respiration yields approximately 36 ATP per glucose molecule.

Question 16

In a scenario where oxygen is not present, which process allows cells to continue producing ATP?

Accepted Answer

Fermentation

Question 17

Which of the following is the correct order of events in aerobic cellular respiration?

Accepted Answer

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

Question 18

Which of the following best explains why the hydrolysis of ATP is considered an exergonic reaction?

Accepted Answer

It releases energy that can be used to drive cellular processes.

Question 19

A plant is exposed to light, but its leaves are deprived of $$CO_2. $$Which process will be directly affected?

Accepted Answer

The Calvin cycle (light-independent reactions)

Question 20

Which of the following is a real-world example of an exergonic reaction in human metabolism?

Accepted Answer

The hydrolysis of ATP to ADP and inorganic phosphate

Cellular Energetics: Enzymes, Energy, and Glycolysis

Study Guide - Practice Questions