Question 1

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

Accepted Answer

Oxygen is the final electron acceptor in the electron transport chain, allowing the chain to operate and ATP to be produced.

Question 2

During glycolysis, what is the net gain of ATP and NADH molecules per molecule of glucose?

Accepted Answer

2 ATP and 2 NADH

Question 3

Which equation correctly represents the overall process of aerobic cellular respiration?

Accepted Answer

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

Question 4

Which process generates the majority of ATP during cellular respiration?

Accepted Answer

Oxidative phosphorylation

Question 5

What is the main purpose of fermentation in cells?

Accepted Answer

To regenerate NAD$^+$ so glycolysis can continue producing ATP

Question 6

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

Accepted Answer

Oxidation is the loss of electrons and reduction is the gain of electrons.

Question 7

A patient is experiencing muscle fatigue due to intense exercise. Which metabolic pathway is most likely responsible for the production of lactic acid in their muscles?

Accepted Answer

Lactic acid fermentation

Question 8

Which molecule acts as an electron carrier by accepting electrons during glycolysis and the citric acid cycle?

Accepted Answer

NAD$^+$

Question 9

In the electron transport chain, what is the direct result of electrons being passed through a series of protein complexes?

Accepted Answer

A proton (H$^+$) gradient is established across the inner mitochondrial membrane.

Question 10

Which of the following best explains why fats are considered excellent sources of energy for cellular respiration?

Accepted Answer

Fats have an abundance of hydrogen atoms, providing many high-energy electrons for redox reactions.

Question 11

Which of the following is true regarding substrate-level phosphorylation?

Accepted Answer

It directly transfers a phosphate group from a substrate to ADP to form ATP.

Question 12

A cell is deprived of oxygen. Which process will continue to produce ATP?

Accepted Answer

Glycolysis

Question 13

Which of the following equations represents the reduction of NAD$^+$ during cellular respiration?

Accepted Answer

$NAD^+ + 2H \rightarrow NADH + H^+$

Question 14

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

Accepted Answer

Glucose $\rightarrow$ NADH (or FADH$_2$) $\rightarrow$ electron transport chain $\rightarrow$ proton-motive force $\rightarrow$ ATP

Question 15

Which of the following statements best explains why fermentation produces much less ATP than aerobic respiration?

Accepted Answer

Fermentation does not utilize the electron transport chain, so only substrate-level phosphorylation occurs.

Question 16

A mutation disables ATP synthase in mitochondria. Which process would be directly affected?

Accepted Answer

Chemiosmosis and oxidative phosphorylation

Question 17

Which of the following is a real-life example of feedback inhibition in cellular respiration?

Accepted Answer

High levels of ATP inhibit an early enzyme in glycolysis, slowing down glucose breakdown.

Question 18

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

Accepted Answer

It completes the breakdown of pyruvate to CO$_2$ and generates NADH and FADH$_2$.

Question 19

Which of the following is a multi-step problem: If a cell metabolizes one molecule of glucose via aerobic respiration, how many ATP molecules are produced, and what percentage of the energy in glucose is transferred to ATP?

Accepted Answer

32 ATP; about 34%

Cellular Respiration and Fermentation (Chapter 9) – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards