Question 1

Which of the following best describes the role of ATP in cellular metabolism?

Accepted Answer

ATP provides energy for cellular work by transferring a phosphate group to other molecules, often via phosphorylation.

Question 2

Which equation correctly represents the exergonic hydrolysis of ATP?

Accepted Answer

$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{ADP} + \mathrm{P}_i$

Question 3

A cell is placed in a closed system where no energy or matter can be exchanged with the surroundings. According to the laws of thermodynamics, what will eventually happen to the cell?

Accepted Answer

The cell will reach equilibrium and die because metabolic reactions cease.

Question 4

Which of the following is an example of an anabolic pathway?

Accepted Answer

Synthesis of proteins from amino acids.

Question 5

Which statement best explains why enzymes are necessary for life?

Accepted Answer

Enzymes lower the activation energy barrier, allowing reactions to occur rapidly at body temperature.

Question 6

A competitive inhibitor affects enzyme activity by:

Accepted Answer

Binding to the active site and preventing substrate binding.

Question 7

Which of the following best illustrates the Second Law of Thermodynamics in biological systems?

Accepted Answer

Some energy from food is lost as heat, increasing the disorder (entropy) of the surroundings.

Question 8

Which of the following would most likely increase the rate of an enzyme-catalyzed reaction that is already saturated with substrate?

Accepted Answer

Adding more enzyme molecules.

Question 9

Which of the following is true about the coupling of catabolic and anabolic pathways in cells?

Accepted Answer

Catabolic pathways provide energy and building blocks for anabolic pathways.

Question 10

Which of the following best describes the effect of a noncompetitive inhibitor on an enzyme?

Accepted Answer

It binds to an alternate site, causing the enzyme's active site to change shape and become less effective.

Question 11

Which of the following is an example of potential energy in a biological system?

Accepted Answer

Energy stored in the covalent bonds of glucose.

Question 12

Which equation represents the endergonic synthesis of ATP from ADP and inorganic phosphate?

Accepted Answer

$\mathrm{ADP} + \mathrm{P}_i \rightarrow \mathrm{ATP} + \mathrm{H}_2\mathrm{O}$

Question 13

A scientist adds an enzyme to a solution of sucrose at room temperature. What is the expected result?

Accepted Answer

The rate of sucrose hydrolysis will increase dramatically.

Question 14

Which of the following statements about enzyme specificity is correct?

Accepted Answer

Enzymes bind to specific substrates due to their unique 3-dimensional structure.

Question 15

Which of the following is a real-world example of the First Law of Thermodynamics?

Accepted Answer

A plant converts sunlight into chemical energy, but the total energy in the system remains constant.

Question 16

Which of the following best explains why cells are considered open systems?

Accepted Answer

Cells exchange both energy and matter with their environment.

Question 17

Which of the following would most likely decrease the activity of an enzyme in the human body?

Accepted Answer

Adding a noncompetitive inhibitor.

Question 18

Which of the following is true about the effect of temperature on enzyme activity?

Accepted Answer

Enzyme activity increases with temperature up to an optimal point, after which it decreases due to denaturation.

Question 19

Which of the following best describes allosteric regulation of enzymes?

Accepted Answer

A regulatory molecule binds to a site other than the active site, altering the enzyme's activity.

Cellular Metabolism, Energy, and Enzyme Function: Study Notes for General Biology

Study Guide - Practice Questions

Study Guide - Flashcards