$$ATP \rightarrow ADP + Pi + \text{energy}$$

Question 1

Which of the following best describes a linear metabolic pathway?

Accepted Answer

A pathway where the product of one reaction becomes the substrate for the next reaction in a sequential manner.

Question 2

What is the primary role of coenzymes such as NAD+ and FADH in cellular respiration?

Accepted Answer

To transfer hydrogen ions and electrons during metabolic reactions.

Question 3

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

Accepted Answer

$$2$$

Question 4

Which of the following statements about anabolic pathways is correct?

Accepted Answer

They require energy to build larger molecules from smaller ones.

Question 5

What is the fate of pyruvate in the presence of oxygen during cellular respiration?

Accepted Answer

It is converted into an acetyl group, producing NADH and CO$$_2.$$

Question 6

Which step of cellular respiration occurs in the cytoplasm?

Accepted Answer

Glycolysis

Question 7

What is the main waste product generated during the preparatory step of cellular respiration?

Accepted Answer

Carbon dioxide ($$CO_2)$$

Question 8

Which of the following best describes substrate-level phosphorylation?

Accepted Answer

The direct transfer of a phosphate group to ADP to form ATP during glycolysis.

Question 9

If oxygen is not present, what happens to the pyruvate produced during glycolysis?

Accepted Answer

It cannot enter the mitochondria and is converted to lactate or ethanol.

Question 10

Which of the following equations correctly represents the breakdown of ATP?

Accepted Answer

$$ATP ightarrow ADP + Pi + 	ext{energy}$$

Question 11

Which molecule acts as the immediate energy currency of the cell?

Accepted Answer

ATP

Question 12

How many NADH molecules are produced during glycolysis from one molecule of glucose?

Accepted Answer

$$2$$

Question 13

Which of the following is NOT a product of the preparatory step in cellular respiration?

Accepted Answer

ATP

Question 14

Which coenzyme is reduced during the preparatory step of cellular respiration?

Accepted Answer

NAD+

Question 15

Which of the following best explains why enzymes are crucial for metabolic pathways?

Accepted Answer

They lower the activation energy required for reactions to proceed.

Question 16

A patient is unable to produce NAD+. Which stage of cellular respiration would be directly affected first?

Accepted Answer

Glycolysis

Question 17

Which of the following statements about catabolic reactions is correct?

Accepted Answer

They release energy by breaking down complex molecules.

Question 18

Which of the following is a correct sequence of events during the preparatory step of cellular respiration?

Accepted Answer

Pyruvate is converted to an acetyl group, CO$$_2 is $$released, NAD+ is reduced, and acetyl CoA is formed.

Question 19

Which of the following best describes the role of Coenzyme A in the preparatory step?

Accepted Answer

It picks up the acetyl group to form acetyl CoA.

Question 20

A mutation prevents the formation of acetyl CoA from pyruvate. Which process would be directly impaired?

Accepted Answer

Entry of carbon into the citric acid cycle.

Metabolic Pathways and Cellular Respiration: Energy Production in Human Cells

Study Guide - Practice Questions