Question 1

Which of the following best describes the overall chemical equation for cellular respiration?

Accepted Answer

$$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6 \ \mathrm{O}_2 ightarrow 6 \ \mathrm{CO}_2 + 6 \ \mathrm{H}_2\mathrm{O} + 	ext{Energy (ATP + heat)}$$

Question 2

During which stage of cellular respiration is the majority of ATP produced?

Accepted Answer

Oxidative phosphorylation (electron transport chain and chemiosmosis)

Question 3

Which of the following statements about redox reactions in cellular respiration is correct?

Accepted Answer

Glucose is oxidized and oxygen is reduced.

Question 4

In the absence of oxygen, which process allows some cells to continue producing ATP?

Accepted Answer

Fermentation

Question 5

Which of the following best explains why glucose is considered a highly reduced molecule?

Accepted Answer

It contains many hydrogen atoms that can be transferred as electrons to other molecules.

Question 6

A patient’s muscle cells are deprived of oxygen during intense exercise. Which product would you expect to accumulate in their muscle tissue?

Accepted Answer

Lactic acid (lactate)

Question 7

Which of the following is a correct description of the fate of pyruvate in the presence of oxygen?

Accepted Answer

It is transported into the mitochondria and converted to acetyl CoA.

Question 8

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 9

Which of the following equations represents the oxidation of glucose during cellular respiration?

Accepted Answer

$$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 \rightarrow 6 \ \mathrm{CO}_2 + 24 \ \mathrm{H}^+ + 24 \ e^-$$

Question 10

Which of the following is a real-world example of an organism using fermentation?

Accepted Answer

Yeast cells producing ethanol and carbon dioxide in the absence of oxygen during bread making.

Question 11

Which of the following statements about catabolic pathways is correct?

Accepted Answer

Catabolic pathways release energy by breaking down complex molecules.

Question 12

Which of the following best describes the function of ATP in cellular respiration?

Accepted Answer

ATP stores energy released from catabolic reactions for use in cellular work.

Question 13

Which of the following is an example of a redox reaction in cellular respiration?

Accepted Answer

NAD$$^+$$ gains electrons to become NADH.

Question 14

A mutation prevents a cell from producing acetyl CoA. Which process would be directly affected?

Accepted Answer

Citric acid cycle (Krebs cycle)

Question 15

Which of the following best explains why energy is lost as heat during cellular respiration?

Accepted Answer

Some energy from glucose is not captured in ATP and is released as heat due to the second law of thermodynamics.

Question 16

Which of the following is true about the role of hydrogen atoms in the oxidation of glucose?

Accepted Answer

Hydrogen atoms are transferred to oxygen, forming water and releasing energy.

Question 17

Which of the following best describes the difference between aerobic and anaerobic respiration?

Accepted Answer

Aerobic respiration uses oxygen as the final electron acceptor, while anaerobic respiration uses other molecules such as sulfate or nitrate.

Question 18

A scientist is studying a new organism that can survive in environments without oxygen by using sulfur as a final electron acceptor. Which process is this organism most likely using?

Accepted Answer

Anaerobic respiration

Question 19

Which of the following is a correct statement about the energy flow in living organisms?

Accepted Answer

Energy flows into an ecosystem as sunlight and leaves as heat.

Question 20

Which of the following best explains why animals must obtain energy from outside sources?

Accepted Answer

Animals are heterotrophs and cannot produce their own food, so they rely on consuming other organisms for energy.

Cellular Respiration & Fermentation: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards