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

Question 1

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

Accepted Answer

$$C_6H_{12}O_6$ + 6O_2 ightarrow 6CO_2 + 6H_2O + 	ext{Energy}$$

Question 2

What is the primary reason glucose is considered an efficient fuel molecule in cellular respiration?

Accepted Answer

It contains many 'hilltop' electrons that can be easily transferred to electron carriers.

Question 3

Which process in cellular respiration produces the most ATP?

Accepted Answer

Oxidative Phosphorylation

Question 4

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

Accepted Answer

Citric Acid Cycle

Question 5

What is the main function of the electron transport chain in mitochondria?

Accepted Answer

To ease the fall of electrons from food to oxygen, releasing energy in small steps

Question 6

Which of the following statements about substrate-level phosphorylation is correct?

Accepted Answer

It involves the direct transfer of a phosphate group from an organic substrate to ADP.

Question 7

Why does FADH2 yield less ATP than NADH during oxidative phosphorylation?

Accepted Answer

FADH2 donates electrons to a lower energy complex in the electron transport chain.

Question 8

What is the fate of pyruvate under anaerobic conditions in human muscle cells?

Accepted Answer

It is converted to lactate.

Question 9

Which of the following best explains why the liver can produce a maximum of 32 ATP per glucose, but the brain only produces 30?

Accepted Answer

The liver uses a shuttle that transfers electrons directly to NAD+, while the brain uses a shuttle that transfers electrons to FAD.

Question 10

Which of the following is NOT a product of the citric acid cycle for each turn?

Accepted Answer

2 ATP

Question 11

What is the role of oxygen in cellular respiration?

Accepted Answer

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

Question 12

Which of the following best describes chemiosmosis in mitochondria?

Accepted Answer

The use of a proton gradient to drive the synthesis of ATP via ATP synthase.

Question 13

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

Accepted Answer

Glucose is oxidized and oxygen is reduced.

Question 14

In alcohol fermentation, what is the final electron acceptor?

Accepted Answer

Acetaldehyde

Question 15

A patient has a genetic defect that prevents the formation of NAD+. Which stage of cellular respiration would be most directly affected?

Accepted Answer

Glycolysis

Question 16

Which of the following best explains why organic molecules with many hydrogen atoms are excellent fuels?

Accepted Answer

Their bonds are a source of electrons that can be easily transferred to oxygen, releasing energy.

Question 17

Which of the following is a direct product of glycolysis?

Accepted Answer

Pyruvate

Question 18

If a toxin inhibited ATP synthase, which process would be directly affected?

Accepted Answer

Chemiosmosis

Question 19

Which of the following is true regarding the energy yield from one molecule of glucose during cellular respiration?

Accepted Answer

About 34% of the energy is used to regenerate ATP, the rest is lost as heat.

Question 20

Which of the following best describes the relationship between photosynthesis and cellular respiration?

Accepted Answer

Photosynthesis stores energy in organic molecules, while cellular respiration releases it.

Cellular Respiration: Harvesting Chemical Energy

Study Guide - Practice Questions