Question 1

Which of the following best describes the structure of the phospholipid bilayer in cell membranes?

Accepted Answer

A double layer of phospholipids with hydrophilic heads facing outward and hydrophobic tails facing inward.

Question 2

Which function is NOT performed by proteins embedded in the cell membrane?

Accepted Answer

Providing structural support to the cell wall.

Question 3

A cell is placed in a solution with a higher concentration of solutes than inside the cell. Which process will most likely occur?

Accepted Answer

Water will move out of the cell by osmosis.

Question 4

Which statement about the fluid mosaic model of cell membranes is correct?

Accepted Answer

Phospholipids and proteins can move laterally within the membrane.

Question 5

Which equation best represents the relationship between surface area and volume as a cell grows?

Accepted Answer

$SA = 6a^2$, $V = a^3$ for a cube$

Question 6

Which of the following is a direct consequence of the selective permeability of the cell membrane?

Accepted Answer

The cell can regulate the movement of ions, nutrients, and waste products.

Question 7

Facilitated diffusion differs from simple diffusion in that:

Accepted Answer

Facilitated diffusion uses membrane proteins to transport molecules across the membrane.

Question 8

Which of the following best explains why cells are generally small in size?

Accepted Answer

Smaller cells have a higher surface area-to-volume ratio, allowing efficient exchange of materials.

Question 9

Which process involves the engulfment of large particles or liquids by the cell membrane to form a vesicle?

Accepted Answer

Endocytosis

Question 10

A patient is given intravenous fluids that are hypotonic compared to their blood plasma. What is the most likely effect on their red blood cells?

Accepted Answer

Red blood cells will swell and may burst due to water influx.

Question 11

Which of the following membrane components is primarily responsible for cell-to-cell recognition?

Accepted Answer

Carbohydrates attached to proteins and lipids

Question 12

Active transport differs from passive transport because:

Accepted Answer

Active transport requires energy, often in the form of ATP.

Question 13

Which of the following is a function of cholesterol in the plasma membrane?

Accepted Answer

It increases membrane fluidity and stability.

Question 14

A cell needs to export large waste products that cannot pass through the membrane by diffusion. Which process will it use?

Accepted Answer

Exocytosis

Question 15

Which of the following best describes the movement of oxygen across the cell membrane?

Accepted Answer

Oxygen moves by simple diffusion down its concentration gradient.

Question 16

Which type of membrane protein is most likely to function as a hormone receptor?

Accepted Answer

Integral protein

Question 17

Which of the following statements about carrier proteins is TRUE?

Accepted Answer

Carrier proteins change shape to move specific molecules across the membrane.

Question 18

If a cell membrane is exposed to very low temperatures, what is the most likely effect?

Accepted Answer

Phospholipids pack tightly, decreasing membrane fluidity.

Question 19

Which of the following best describes the role of the glycocalyx in the plasma membrane?

Accepted Answer

It is involved in cell recognition, communication, and adhesion.

Question 20

Which of the following is NOT a function of the plasma membrane?

Accepted Answer

Providing rigid structural support to the cell wall.

Cell Membranes: Structure, Function, and Transport Mechanisms

Study Guide - Practice Questions