Question 1

Which of the following best describes the effect of temperature on enzyme activity?

Accepted Answer

Enzyme activity increases with temperature up to an optimal point, then decreases as the enzyme denatures.

Question 2

A scientist adds a molecule that binds to the active site of an enzyme, preventing substrate binding. What type of inhibition is this?

Accepted Answer

Competitive inhibition

Question 3

Which equation correctly represents the net ATP yield from glycolysis per molecule of glucose?

Accepted Answer

$$ATP_{net} = 2$$

Question 4

During feedback inhibition, which of the following occurs in a metabolic pathway?

Accepted Answer

The final product binds to an enzyme early in the pathway, decreasing its activity.

Question 5

Which of the following best describes the difference between competitive and non-competitive enzyme inhibitors?

Accepted Answer

Competitive inhibitors bind to the active site, while non-competitive inhibitors bind elsewhere on the enzyme.

Question 6

Which of the following is the correct input and output for glycolysis?

Accepted Answer

Input: Glucose; Output: Pyruvate, ATP, NADH

Question 7

In cellular respiration, what is the total number of ATP molecules produced per molecule of pyruvate (assuming aerobic conditions)?

Accepted Answer

$$ATP_{total} = 12.5$$

Question 8

A marathon runner relies on aerobic catabolism of glucose. Which of the following is a correct comparison to anaerobic catabolism?

Accepted Answer

Aerobic catabolism produces more ATP and less lactic acid than anaerobic catabolism.

Question 9

If the pH of a solution containing an enzyme is changed from its optimal value, what is the most likely effect?

Accepted Answer

The enzyme will denature and lose activity.

Question 10

Which of the following best explains why feedback inhibition is important in metabolic pathways?

Accepted Answer

It prevents the accumulation of excess product and conserves resources.

Question 11

A patient with a genetic mutation produces an enzyme that cannot be inhibited by its pathway's final product. What is the most likely consequence?

Accepted Answer

The pathway will produce more product than normal, possibly leading to toxicity.

Question 12

Which formula best represents the overall reaction for aerobic cellular respiration of glucose?

Accepted Answer

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

Question 13

During intense exercise, muscle cells switch to anaerobic metabolism. What is the primary product of glucose catabolism under these conditions?

Accepted Answer

Lactic acid

Question 14

Which of the following scenarios best illustrates non-competitive inhibition?

Accepted Answer

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

Question 15

If a cell is deprived of oxygen, which process will be most affected?

Accepted Answer

Aerobic cellular respiration

Question 16

Which of the following is a correct statement about ATP production in glycolysis and cellular respiration?

Accepted Answer

Aerobic respiration produces significantly more ATP than glycolysis.

Question 17

A researcher observes that an enzyme's activity plateaus even as substrate concentration increases. Which explanation is most likely?

Accepted Answer

The enzyme has reached saturation; all active sites are occupied.

Question 18

Which of the following is a real-world example of feedback inhibition?

Accepted Answer

ATP inhibiting phosphofructokinase in glycolysis when energy is abundant.

Question 19

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

Accepted Answer

Enzymes have active sites with shapes complementary to specific substrates.

Question 20

A patient is diagnosed with acidosis, lowering their blood pH. What is the most likely effect on their enzymes?

Accepted Answer

Enzyme activity will decrease due to denaturation at non-optimal pH.

BIO 101 Chapters 4-6: Enzymes, Cellular Respiration, and Metabolic Pathways Study Guide

Study Guide - Practice Questions