Q: Which of the following equations correctly represents the overall reaction of aerobic cellular respiration?

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

Question 1

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

Accepted Answer

Oxygen is the final electron acceptor in the electron transport chain.

Question 2

During glycolysis, glucose ($$C_6H_{12}O_6$) is broken down into which molecule, and how many are produced per glucose?

Accepted Answer

Two molecules of pyruvate

Question 3

Which process in cellular respiration directly produces the most ATP per glucose molecule?

Accepted Answer

Oxidative phosphorylation

Question 4

What is the main purpose of the proton (H$$^+) $$gradient created by the electron transport chain?

Accepted Answer

To drive the synthesis of ATP via ATP synthase

Question 5

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

Accepted Answer

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

Question 6

If a cell is deprived of oxygen, which process will continue to produce ATP?

Accepted Answer

Glycolysis

Question 7

Which molecule is regenerated during fermentation to allow glycolysis to continue in the absence of oxygen?

Accepted Answer

NAD$$^+$$

Question 8

A marathon runner relies primarily on which metabolic pathway to sustain muscle activity over long distances?

Accepted Answer

Oxidative metabolism (cellular respiration)

Question 9

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

Accepted Answer

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

Question 10

During the citric acid cycle, acetyl CoA combines with which molecule to form citrate?

Accepted Answer

Oxaloacetate

Question 11

Which of the following is a correct sequence of energy flow during cellular respiration?

Accepted Answer

Glucose $$\rightarrow$$ NADH $$\rightarrow$$ electron transport chain $$\rightarrow$$ proton-motive force $$\rightarrow$$ ATP

Question 12

Which of the following is NOT a product of the citric acid cycle per glucose molecule?

Accepted Answer

Glucose

Question 13

What is the efficiency of cellular respiration in converting the energy in glucose to ATP, given the following: hydrolysis of ATP yields $$31	ext{ kJ/mol}$$, $$38$$ ATP produced per glucose, and oxidation of glucose contains $$2870	ext{ kJ/mol} of $$energy?

Accepted Answer

$$\frac{1178}{2870} \approx 41\%$$

Question 14

Which of the following best explains why fermentation is less efficient than aerobic respiration?

Accepted Answer

Fermentation produces only 2 ATP per glucose, while aerobic respiration produces up to 38 ATP.

Question 15

Which of the following statements about facultative anaerobes is correct?

Accepted Answer

They can switch between aerobic and anaerobic respiration depending on oxygen availability.

Question 16

Which of the following molecules can be used as fuel for cellular respiration, besides glucose?

Accepted Answer

Glucose, fructose, and amino acids

Question 17

What happens when hydrogen ions are pumped from the mitochondrial matrix across the inner membrane into the intermembrane space?

Accepted Answer

A proton gradient is created, which drives ATP synthesis.

Question 18

Which of the following is a real-life consequence of lactic acid fermentation in human muscle cells?

Accepted Answer

Lactate buildup can cause muscle fatigue during sprints.

Question 19

Which of the following statements about compartmentalization in eukaryotic cells is correct?

Accepted Answer

It allows specific metabolic processes to occur in specialized regions.

Question 20

Which of the following is the correct description of chemiosmosis?

Accepted Answer

The use of energy in a H$$^+$$ gradient to drive cellular work, such as ATP synthesis.

Cellular Respiration: Mechanisms and Importance in Biology

Study Guide - Practice Questions

Study Guide - Flashcards