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

Question 1

Which of the following best describes the main function of the electron transport chain in cellular respiration?

Accepted Answer

To create a proton gradient across the inner mitochondrial membrane

Question 2

During oxidative phosphorylation, what is the final electron acceptor in the electron transport chain?

Accepted Answer

Oxygen ($$O_2)$$

Question 3

Which process occurs in the cytoplasm and does not require oxygen?

Accepted Answer

Glycolysis

Question 4

What is the net gain of ATP molecules produced directly by glycolysis from one molecule of glucose?

Accepted Answer

$$2$$

Question 5

Which of the following best explains why NADH produces more ATP than FADH$$_2$$ during oxidative phosphorylation?

Accepted Answer

NADH donates electrons earlier in the electron transport chain, allowing more protons to be pumped

Question 6

A patient is exposed to a toxin that inhibits ATP synthase. Which of the following would most likely occur?

Accepted Answer

ATP production by chemiosmosis would decrease

Question 7

Which of the following is a key difference between fermentation and aerobic respiration?

Accepted Answer

Fermentation uses an organic molecule as the final electron acceptor

Question 8

Which enzyme is responsible for regulating the rate of glycolysis?

Accepted Answer

Phosphofructokinase

Question 9

In the absence of oxygen, muscle cells can continue to produce ATP by converting pyruvate into which molecule?

Accepted Answer

Lactic acid

Question 10

Which of the following best describes chemiosmosis in mitochondria?

Accepted Answer

The synthesis of ATP using the energy of a proton gradient

Question 11

If a mutation prevents the regeneration of NAD$$^+$$ during fermentation, what would be the immediate consequence for the cell?

Accepted Answer

Glycolysis would stop due to lack of NAD$$^+$$

Question 12

Which of the following is a product of the citric acid cycle for each acetyl-CoA that enters?

Accepted Answer

$$3$$ NADH

Question 13

Which step in cellular respiration is responsible for the majority of ATP production?

Accepted Answer

Oxidative phosphorylation

Question 14

Which of the following statements about the electron transport chain is correct?

Accepted Answer

It creates a proton gradient used by ATP synthase

Question 15

A person is exposed to cyanide, which blocks the transfer of electrons to oxygen in the electron transport chain. What is the most immediate effect?

Accepted Answer

NADH and FADH$$_2$$ will accumulate

Question 16

Which of the following best explains why fats yield more ATP per gram than carbohydrates?

Accepted Answer

Fats have more hydrogen atoms, providing more electrons for the electron transport chain

Question 17

Which of the following is NOT a product of fermentation?

Accepted Answer

Acetyl-CoA

Question 18

Which of the following equations correctly represents the overall process of aerobic cellular respiration?

Accepted Answer

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

Question 19

Which of the following best describes the role of oxygen in cellular respiration?

Accepted Answer

It acts as the final electron acceptor in the electron transport chain

Question 20

Which of the following statements about anaerobic respiration is correct?

Accepted Answer

It can use molecules other than oxygen as the final electron acceptor

Cellular Respiration: Oxidative Phosphorylation, Anaerobic Respiration, and Fermentation

Study Guide - Practice Questions