Question 1

Which of the following best describes the fluid mosaic model of the plasma membrane?

Accepted Answer

A dynamic structure with proteins embedded in or attached to a bilayer of phospholipids that can move laterally.

Question 2

A red blood cell is placed in a hypotonic solution. What will most likely happen to the cell, and why?

Accepted Answer

It will swell and possibly burst because water will move into the cell by osmosis.

Question 3

Which of the following statements about membrane proteins is correct?

Accepted Answer

Integral proteins are embedded within the lipid bilayer and may span the membrane.

Question 4

Which of the following best explains why cholesterol is important in animal cell membranes?

Accepted Answer

It prevents the phospholipids from packing too closely, thus maintaining membrane fluidity.

Question 5

A cell is placed in an isotonic solution. Which of the following will occur?

Accepted Answer

There will be no net movement of water into or out of the cell.

Question 6

Which of the following is an example of active transport across a cell membrane?

Accepted Answer

Movement of sodium ions against their concentration gradient using the sodium-potassium pump.

Question 7

Which equation correctly represents the relationship between free energy ($$G$$), enthalpy ($$H$$), entropy ($$S$$), and temperature ($$T$$)?

Accepted Answer

$$ G = H - TS $$

Question 8

During cellular respiration, which stage produces the most ATP per molecule of glucose?

Accepted Answer

Electron transport chain and oxidative phosphorylation

Question 9

Which of the following best describes an exergonic reaction?

Accepted Answer

A reaction that releases energy to the environment and has a negative $$\Delta G.$$

Question 10

Which of the following statements about enzymes is correct?

Accepted Answer

Enzymes lower the activation energy, allowing reactions to proceed more rapidly.

Question 11

A plant cell is placed in a hypertonic solution. What is the most likely outcome?

Accepted Answer

The cell will lose water, and the plasma membrane will pull away from the cell wall (plasmolysis).

Question 12

Which of the following is a correct description of facilitated diffusion?

Accepted Answer

It involves the movement of substances through the membrane via carrier proteins, down their concentration gradient, without energy input.

Question 13

Which of the following best explains the role of turgor pressure in plant cells?

Accepted Answer

It is responsible for the rigidity and support of non-woody plant tissues.

Question 14

Which of the following is an example of a coupled reaction in cellular metabolism?

Accepted Answer

The hydrolysis of ATP providing energy for the active transport of ions across a membrane.

Question 15

Which of the following statements about the sodium-potassium pump is correct?

Accepted Answer

It requires ATP to move sodium ions out of the cell and potassium ions into the cell against their gradients.

Question 16

Which of the following best describes the process of receptor-mediated endocytosis?

Accepted Answer

The cell takes in specific molecules after they bind to receptors on the cell surface, leading to vesicle formation.

Question 17

Which of the following factors would NOT increase the rate of an enzyme-catalyzed reaction?

Accepted Answer

Adding a noncompetitive inhibitor.

Question 18

Which of the following is true regarding the second law of thermodynamics?

Accepted Answer

All systems tend toward increased disorder (entropy) over time.

Question 19

Which of the following best describes the induced fit hypothesis of enzyme function?

Accepted Answer

The enzyme's active site changes shape to better fit the substrate upon binding.

Membrane Structure, Function, and Metabolism: General Biology Study Notes

Study Guide - Practice Questions