$$\text{Pyruvate} + \text{CoA-SH} + \text{NAD}^+ \rightarrow \text{Acetyl CoA} + \text{CO}_2 + \text{NADH}$$

Question 1

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

Accepted Answer

Oxygen is the final electron acceptor in the electron transport chain, allowing the formation of water.

Question 2

During the citric acid cycle, how many NADH molecules are produced per glucose molecule?

Accepted Answer

6 NADH

Question 3

Which equation correctly represents the overall reaction for aerobic respiration of one glucose molecule?

Accepted Answer

$$\mathrm{C_6H_{12}O_6$} + 6\mathrm{O_2$} \rightarrow 6\mathrm{CO_2$} + 6\mathrm{H_2O} + 38\mathrm{ATP}$$

Question 4

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

Accepted Answer

To pump protons across the inner mitochondrial membrane, creating a proton gradient.

Question 5

Which of the following statements about ATP synthase is correct?

Accepted Answer

ATP synthase uses the energy from the proton gradient to phosphorylate ADP to ATP.

Question 6

If a mutation prevented the formation of porins in the mitochondrial outer membrane, which process would be directly affected?

Accepted Answer

Transport of pyruvate into the mitochondrial matrix.

Question 7

Which step in aerobic respiration is responsible for the largest production of ATP?

Accepted Answer

Electron transport chain and oxidative phosphorylation

Question 8

How many ATP molecules are produced directly from glycolysis per glucose molecule?

Accepted Answer

2 ATP

Question 9

Which of the following best explains why protons cannot freely diffuse across the inner mitochondrial membrane?

Accepted Answer

The inner membrane is impermeable to ions, including protons, due to its lipid composition.

Question 10

Which of the following is a correct summary of the products generated from the complete oxidation of one glucose molecule in aerobic respiration?

Accepted Answer

6 CO2, 6 H2O, 38 ATP

Question 11

Which of the following reactions occurs during pyruvate oxidation?

Accepted Answer

$$	ext{Pyruvate} + 	ext{CoA-SH} + 	ext{NAD}^+ ightarrow 	ext{Acetyl CoA} + 	ext{CO}_2 + 	ext{NADH}$$

Question 12

Which molecule enters the citric acid cycle and is completely oxidized to CO2?

Accepted Answer

Acetyl CoA

Question 13

What is the significance of the proton motive force (PMF) in mitochondria?

Accepted Answer

It provides the energy required for ATP synthesis by ATP synthase.

Question 14

Which of the following best describes the arrangement of electron carriers in the electron transport chain?

Accepted Answer

Electron carriers are arranged by their redox potential, with the strongest electron donors at the beginning and the best acceptors at the end.

Question 15

A patient is diagnosed with a genetic defect that impairs the function of ATP synthase. Which of the following would most likely occur?

Accepted Answer

The patient would be unable to efficiently produce ATP from the proton gradient, leading to cellular energy deficiency.

Question 16

Which of the following is NOT a product of the citric acid cycle per acetyl CoA?

Accepted Answer

2 ATP

Question 17

Which of the following best explains why cells die in the absence of oxygen?

Accepted Answer

Without oxygen, the electron transport chain cannot function, preventing ATP synthesis and causing cell death.

Question 18

How many molecules of ATP are produced from the oxidation of one molecule of glucose in aerobic respiration?

Accepted Answer

38 ATP

Question 19

Which of the following statements about the citric acid cycle is correct?

Accepted Answer

The citric acid cycle regenerates oxaloacetate at the end of each turn.

Aerobic Respiration: The Complete Oxidation of Glucose in Eukaryotic Cells

Study Guide - Practice Questions