Question 1

Which structure within the mitochondrion is primarily responsible for increasing the surface area available for electron transport and ATP synthesis?

Accepted Answer

Cristae

Question 2

During aerobic respiration, which molecule acts as the terminal electron acceptor in the electron transport chain?

Accepted Answer

O$$_2$$

Question 3

Which equation best represents the complete oxidation of glucose during aerobic respiration?

Accepted Answer

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

Question 4

What is the maximum theoretical ATP yield per molecule of glucose in aerobic respiration in most prokaryotes?

Accepted Answer

38 ATP

Question 5

Which process directly generates ATP in the citric acid cycle?

Accepted Answer

Substrate-level phosphorylation

Question 6

In eukaryotic cells, what is the main reason the actual ATP yield from aerobic respiration is often lower than the theoretical maximum?

Accepted Answer

Loss of citric acid cycle intermediates, proton leakage, and use of protons for other transport processes

Question 7

Which of the following is a correct summary of the ATP yield from NADH and FADH$$_2$$ oxidation in the electron transport chain?

Accepted Answer

Each NADH yields 3 ATP, each FADH$$_2$$ yields 2 ATP

Question 8

Which step in aerobic respiration occurs in the cytosol of eukaryotic cells?

Accepted Answer

Glycolysis

Question 9

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

Accepted Answer

It pumps protons across the inner mitochondrial membrane to create a gradient

Question 10

Which molecules act as activators of citric acid cycle enzymes?

Accepted Answer

NAD$$^+$$, AMP, ADP, CoA

Question 11

Fatty acids are catabolized in the mitochondria by which process, and what is the main product that enters the citric acid cycle?

Accepted Answer

β-oxidation; acetyl CoA

Question 12

Which of the following best explains how the exergonic 'slide' of electrons down the electron transport chain is coupled to ATP production?

Accepted Answer

Electron flow powers proton pumping, creating a gradient used by ATP synthase

Question 13

Which equation represents the ATP synthesis driven by the electron transport chain and chemiosmosis?

Accepted Answer

$$\mathrm{ADP + P_i \rightarrow ATP}$$

Question 14

Which component of the ATP synthase complex is embedded in the inner mitochondrial membrane and acts as a proton channel?

Accepted Answer

Fo

Question 15

A mutation disrupts the function of the TOM complex in mitochondria. Which process would be most directly affected?

Accepted Answer

Import of polypeptides from the cytosol into mitochondria

Question 16

Which of the following is a product of the reduction of oxygen at the end of the electron transport chain?

Accepted Answer

H$$_2O$$

Question 17

In the context of aerobic respiration, which shuttle mechanism can reduce the theoretical ATP yield from 38 to 36 in some eukaryotic cells?

Accepted Answer

Glycerol phosphate shuttle

Question 18

Which of the following statements about the permeability of mitochondrial membranes is correct?

Accepted Answer

The outer membrane is permeable due to porins, while the inner membrane is a significant permeability barrier

Question 19

Which respiratory complexes in the electron transport chain are responsible for proton pumping?

Accepted Answer

Complexes I, III, and IV

Question 20

A patient has a genetic defect that causes excessive proton leakage across the inner mitochondrial membrane. What is the most likely consequence?

Accepted Answer

Decreased ATP production

Ch 10a: Aerobic Respiration: Chemotropic Energy Metabolism in Eukaryotic Cells

Study Guide - Practice Questions