$$\text{Glucose} \rightarrow 2 \text{Pyruvate} + 2 \text{ATP} + 2 \text{NADH}$$

$$\text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \rightarrow 6\text{CO}_2 + 6\text{H}_2\text{O} + \text{ATP}$$

Question 1

Which of the following best describes the role of pyruvate dehydrogenase in cellular respiration?

Accepted Answer

It catalyzes the oxidative decarboxylation of pyruvate to acetyl CoA, producing NADH and CO$$_2.$$

Question 2

During the complete oxidation of one molecule of glucose in eukaryotic cells, how many net ATP molecules are typically produced?

Accepted Answer

$$30$$

Question 3

Which process is responsible for creating the proton-motive force used by ATP synthase?

Accepted Answer

Electron transport chain

Question 4

Fatty acids are broken down by $$eta-$$oxidation. What is the main product that enters the citric acid cycle from this process?

Accepted Answer

Acetyl CoA

Question 5

In the absence of oxygen, which pathway do cells use to produce ATP?

Accepted Answer

Fermentation

Question 6

Which of the following statements about fermentation is correct?

Accepted Answer

Fermentation produces only 2 ATP per glucose molecule.

Question 7

What is the primary function of the citric acid cycle in cellular respiration?

Accepted Answer

To complete the oxidation of carbon atoms from food, generating NADH, FADH$$_2$$, and CO$$_2$$

Question 8

Which molecule acts as the final electron acceptor in the mitochondrial electron transport chain?

Accepted Answer

O$$_2$$

Question 9

If a cell is unable to transport pyruvate into the mitochondria, which process will be directly affected?

Accepted Answer

Citric acid cycle

Question 10

Which of the following equations correctly represents the net products of glycolysis per molecule of glucose?

Accepted Answer

$$	ext{Glucose} ightarrow 2 	ext{Pyruvate} + 2 	ext{ATP} + 2 	ext{NADH}$$

Question 11

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

Accepted Answer

Fermentation does not fully oxidize glucose, resulting in less ATP production.

Question 12

What is the main reason some organisms switch to fermentation when oxygen is unavailable?

Accepted Answer

To regenerate NAD$$^+$$ for glycolysis to continue

Question 13

Which of the following is a direct product of the citric acid cycle per glucose molecule?

Accepted Answer

$$6$$ NADH

Question 14

In lactic acid fermentation, which molecule accepts electrons from NADH?

Accepted Answer

Pyruvate

Question 15

Which of the following best describes chemiosmosis?

Accepted Answer

The synthesis of ATP using energy released by the flow of H$$^+$$ down its electrochemical gradient

Question 16

Which process occurs in the cytosol of eukaryotic cells?

Accepted Answer

Glycolysis

Question 17

What is the main function of the proton-motive force in mitochondria?

Accepted Answer

To drive the synthesis of ATP by ATP synthase

Question 18

Which of the following is true about the location of pyruvate processing in prokaryotes?

Accepted Answer

It occurs in the cytosol.

Question 19

Which of the following is a correct summary equation for the complete oxidation of glucose in cellular respiration?

Accepted Answer

$$	ext{C}_6	ext{H}_{12}	ext{O}_6 + 6	ext{O}_2 ightarrow 6	ext{CO}_2 + 6	ext{H}_2	ext{O} + 	ext{ATP}$$

Question 20

Which of the following is a key difference between lactic acid fermentation and alcohol fermentation?

Accepted Answer

Alcohol fermentation produces ethanol and CO$$_2$$, while lactic acid fermentation produces lactate.

Cellular Respiration & Fermentation: Mechanisms of ATP Production in Cells

Study Guide - Practice Questions