Q: Which equation correctly represents the hydrolysis of ATP?

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

Question 1

Which of the following best describes the Fluid-Mosaic Model of the plasma membrane?

Accepted Answer

A flexible bilayer of phospholipids with proteins and carbohydrates embedded and moving laterally.

Question 2

A red blood cell is placed in a solution and swells until it bursts. Which type of solution is the cell in, and what is the direction of water movement?

Accepted Answer

Hypotonic; water moves into the cell.

Question 3

Which of the following transport mechanisms requires energy input from the cell and moves substances against their concentration gradient?

Accepted Answer

Active transport

Question 4

Which statement correctly applies the first law of thermodynamics to living organisms?

Accepted Answer

Cells convert energy from one form to another, but total energy remains constant.

Question 5

A cell uses exocytosis to secrete insulin into the bloodstream. Which of the following best describes this process?

Accepted Answer

Insulin is packaged in vesicles that fuse with the plasma membrane, releasing contents outside the cell.

Question 6

Which of the following is an example of an exergonic reaction?

Accepted Answer

ATP hydrolysis to ADP and inorganic phosphate

Question 7

Which equation correctly represents the hydrolysis of ATP?

Accepted Answer

$$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} ightarrow \mathrm{ADP} + \mathrm{P}_i + 	ext{energy}$$

Question 8

Which of the following best describes the role of enzymes in biological reactions?

Accepted Answer

Enzymes lower the activation energy, increasing the rate of reactions.

Question 9

A competitive inhibitor affects an enzyme by:

Accepted Answer

Binding to the active site and blocking substrate binding.

Question 10

Which of the following graphs best represents the effect of increasing substrate concentration on enzyme activity, assuming enzyme concentration is constant?

Accepted Answer

A curve that rises quickly and then levels off at a maximum rate.

Question 11

Which of the following statements about energy coupling in cells is correct?

Accepted Answer

Energy coupling allows endergonic reactions to occur by pairing them with exergonic reactions.

Question 12

Which of the following best describes the difference between simple diffusion and facilitated diffusion?

Accepted Answer

Facilitated diffusion uses membrane proteins to transport substances, while simple diffusion does not.

Question 13

A cell is placed in a hypertonic solution. What will happen to the cell, and why?

Accepted Answer

The cell will shrink because water leaves the cell.

Question 14

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

Accepted Answer

A molecule of glucose before it is metabolized.

Question 15

Which of the following best describes feedback inhibition in metabolic pathways?

Accepted Answer

The final product of a pathway inhibits an enzyme involved early in the pathway.

Question 16

Which of the following statements about the second law of thermodynamics is correct?

Accepted Answer

Energy transformations increase the entropy (disorder) of the universe.

Question 17

Which of the following is true regarding the ATP/ADP cycle?

Accepted Answer

ATP hydrolysis releases energy that can be used for cellular work.

Question 18

Which of the following best describes the mechanism of allosteric inhibition?

Accepted Answer

An inhibitor binds to a site other than the active site, changing the enzyme's shape and reducing activity.

Question 19

Which of the following is a correct comparison between endergonic and exergonic reactions?

Accepted Answer

Exergonic reactions have products with lower energy than reactants; endergonic reactions have products with higher energy than reactants.

Question 20

Which of the following terms refers to a non-protein molecule that assists enzyme function, such as a vitamin-derived molecule?

Accepted Answer

Coenzyme

Chapter 5: The Working Cell – Study Guide and Key Concepts

Study Guide - Practice Questions

Study Guide - Flashcards