Question 1

Which of the following best describes the overall reaction for cellular respiration, and what is the fate of glucose in this process?

$$\mathrm{C_6H_{12}O_6$ + 6O_2 ightarrow 6CO_2 + 6H_2O + 	ext{energy}}$$

Accepted Answer

Glucose is oxidized to form carbon dioxide, and oxygen is reduced to form water.

Question 2

During which stage of cellular respiration is the majority of ATP produced, and what is the main process responsible for this ATP synthesis?

Accepted Answer

Electron transport chain; oxidative phosphorylation

Question 3

Which molecule acts as the final electron acceptor in the mitochondrial electron transport chain, and what is the product formed?

Accepted Answer

O$$_2$$; H$$_2O$$

Question 4

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 5

In glycolysis, what are the net products generated from one molecule of glucose?

Accepted Answer

2 pyruvate, 2 ATP, 2 NADH

Question 6

Which process links glycolysis to the citric acid cycle, and what are its main outputs per glucose molecule?

Accepted Answer

Pyruvate oxidation; 2 acetyl-CoA, 2 NADH, 2 CO$$_2$$

Question 7

Which of the following best explains why plants are considered autotrophs?

Accepted Answer

They use sunlight to convert CO$$_2$$ into glucose.

Question 8

What is the primary role of NADH and FADH$$_2 in $$cellular respiration?

Accepted Answer

They carry high-energy electrons to the electron transport chain.

Question 9

Which of the following equations correctly represents the net reaction of glycolysis?

$$\mathrm{C_6H_{12}O_6$ + 2NAD^+ + 2ADP + 2P_i \rightarrow 2C_3H_4O_3 + 2NADH + 2H^+ + 2ATP + 2H_2O}$$

Accepted Answer

Glycolysis produces 2 pyruvate, 2 NADH, and 2 ATP per glucose.

Question 10

Which of the following best describes substrate-level phosphorylation?

Accepted Answer

ATP is produced directly by transferring a phosphate group from a substrate to ADP.

Question 11

During the citric acid cycle, which molecule is regenerated to allow the cycle to continue, and what is its carbon number?

Accepted Answer

Oxaloacetate; 4 carbons

Question 12

Which of the following is a correct description of the flow of carbon during cellular respiration?

Accepted Answer

Glucose (6C) → 2 Pyruvate (3C) → 2 Acetyl-CoA (2C) + 2 CO$$_2$$ → 4 CO$$_2 ($$from citric acid cycle)

Question 13

Which of the following best explains why the oxidation of glucose is energetically favorable?

Accepted Answer

The products (CO$$_2$$ and H$$_2O) $$are at a lower free energy state than the reactants.

Question 14

Which of the following is a correct pairing of process and location in eukaryotic cells?

Accepted Answer

Citric acid cycle – mitochondrial matrix

Question 15

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

Accepted Answer

It acts as the final electron acceptor in the electron transport chain.

Question 16

Which of the following is a correct description of the relationship between photosynthesis and cellular respiration in the biosphere?

Accepted Answer

Photosynthesis stores energy in glucose, and cellular respiration releases energy from glucose.

Question 17

Which of the following best explains why NAD$$^+ is $$essential for glycolysis to continue?

Accepted Answer

NAD$$^+$$ accepts electrons during glycolysis, allowing ATP production to continue.

Question 18

Which of the following best describes the fate of the carbons from glucose during aerobic respiration?

Accepted Answer

They are released as CO$$_2$$ during pyruvate oxidation and the citric acid cycle.

Question 19

Which of the following is a real-life example of substrate-level phosphorylation?

Accepted Answer

The direct transfer of a phosphate group from phosphoenolpyruvate (PEP) to ADP during glycolysis.

Cellular Respiration: Carbohydrate Oxidation and Energy Production

Study Guide - Practice Questions