Question 1

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

Accepted Answer

A flexible bilayer of phospholipids with embedded proteins that move freely, creating a constantly changing pattern.

Question 2

Which of the following is a function of the glycocalyx on the cell surface?

Accepted Answer

Acting as a biological marker for cell-to-cell recognition.

Question 3

A red blood cell is placed in a solution and begins to swell and eventually bursts. Which type of solution was the cell placed in?

Accepted Answer

Hypotonic solution

Question 4

Which of the following best explains why oxygen and carbon dioxide can easily diffuse across the plasma membrane?

Accepted Answer

They are nonpolar and lipid-soluble.

Question 5

Which cell junction would be most important in tissues that experience significant mechanical stress, such as cardiac muscle?

Accepted Answer

Desmosomes

Question 6

A solution contains 1 M NaCl. What is its osmolarity?

Accepted Answer

$$2~	ext{osmol/L}$$

Question 7

Which of the following statements about facilitated diffusion is correct?

Accepted Answer

It uses carrier or channel proteins to move substances down their concentration gradient.

Question 8

What would happen to a cell placed in a hypertonic solution?

Accepted Answer

It would shrink due to water loss.

Question 9

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

Accepted Answer

Forming the glycocalyx

Question 10

Which of the following best describes osmosis?

Accepted Answer

Movement of water from an area of low solute concentration to high solute concentration across a selectively permeable membrane.

Question 11

A patient receives an intravenous solution that is hypotonic relative to their blood plasma. What is the most likely effect on their red blood cells?

Accepted Answer

Cells will swell and may burst (lyse).

Question 12

Which of the following is true regarding the structure of phospholipids in the plasma membrane?

Accepted Answer

The phosphate heads are hydrophilic and face the aqueous environments inside and outside the cell.

Question 13

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

Accepted Answer

Integral protein

Question 14

Which of the following best explains why burn patients are at risk of losing fluids and electrolytes?

Accepted Answer

Their plasma membranes are damaged, allowing substances to diffuse freely in and out of cells.

Question 15

Which of the following is a characteristic of carrier-mediated facilitated diffusion?

Accepted Answer

It is limited by the number of available carriers, leading to saturation.

Question 16

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

Accepted Answer

It increases membrane stability.

Question 17

Which of the following cell junctions allows for the rapid passage of ions and electrical signals between cardiac muscle cells?

Accepted Answer

Gap junctions

Question 18

A solution contains 0.5 M glucose and 0.5 M NaCl. What is the total osmolarity of the solution?

Accepted Answer

$$1.5~	ext{osmol/L}$$

Question 19

Which of the following is NOT a property of simple diffusion across the plasma membrane?

Accepted Answer

It requires a protein carrier.

Question 20

Which of the following best describes the relationship between hydrostatic pressure and osmotic pressure in animal cells?

Accepted Answer

When hydrostatic pressure equals osmotic pressure, there is no further net movement of water.

Cells: The Living Units – Structure and Function of the Plasma Membrane

Study Guide - Practice Questions