Question 1

Which of the following best describes the function of the plasma membrane in animal cells?

Accepted Answer

It physically isolates the cell, provides structural support, communicates with other cells, regulates transport, and identifies the cell.

Question 2

A red blood cell is placed in a hypertonic solution. What is the most likely outcome, and why?

Accepted Answer

The cell will lose water and shrivel (crenate) because the extracellular fluid has a greater ability to cause osmosis.

Question 3

Which of the following statements about osmosis is correct?

Accepted Answer

Osmosis is the movement of solvent (water) across a selectively permeable membrane from a region of lower solute concentration to higher solute concentration.

Question 4

Which of the following best explains the role of the sodium-potassium pump ($$\mathrm{Na^+/K^+}$$ ATPase) in maintaining cellular homeostasis?

Accepted Answer

It moves 3 sodium ions out of the cell and 2 potassium ions into the cell against their concentration gradients using ATP.

Question 5

A patient is given an intravenous solution that is hypotonic relative to their blood plasma. What is the physiological risk associated with this treatment?

Accepted Answer

Red blood cells may gain water, swell, and potentially lyse.

Question 6

Which of the following is a key difference between simple diffusion and facilitated diffusion across the plasma membrane?

Accepted Answer

Facilitated diffusion requires membrane proteins to transport polar or charged solutes, while simple diffusion does not.

Question 7

Which of the following best describes secondary active transport?

Accepted Answer

It couples the active transport of one substance with the passive transport of another, using the energy from the concentration gradient created by primary active transport.

Question 8

A cell is placed in an isotonic solution. What will happen to the cell's volume, and why?

Accepted Answer

The cell's volume will remain unchanged because there is no net movement of water.

Question 9

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

Accepted Answer

Storing genetic information for the cell.

Question 10

A pharmaceutical company develops a drug that binds to a membrane receptor and blocks the action of the natural ligand. This drug is best described as:

Accepted Answer

An antagonist

Question 11

Which of the following best explains why cholesterol is important in the plasma membrane?

Accepted Answer

It stabilizes the structure of the membrane when temperature changes.

Question 12

During phagocytosis, which of the following occurs?

Accepted Answer

The cell engulfs large particles such as bacteria or dead cells using vesicles.

Question 13

Which of the following statements about the fluid mosaic model of the plasma membrane is correct?

Accepted Answer

The membrane is composed of a phospholipid bilayer with proteins, lipids, and carbohydrates that move laterally, giving it fluidity.

Question 14

A cell is exposed to a toxin that inhibits the function of aquaporins. What is the most likely effect on the cell?

Accepted Answer

The cell's ability to rapidly transport water across the membrane will be impaired.

Question 15

Which of the following best describes the difference between endocytosis and exocytosis?

Accepted Answer

Endocytosis brings substances into the cell using vesicles, while exocytosis releases substances from the cell.

Question 16

Which of the following scenarios best illustrates the concept of secondary active transport?

Accepted Answer

A sodium gradient established by the $$\mathrm{Na^+/K^+}$$ pump is used to transport glucose into the cell against its concentration gradient.

Question 17

Which of the following is a property of the cytoskeleton?

Accepted Answer

It creates and maintains cell shape, holds organelles in place, and provides transportation for substances within the cell.

Question 18

A cell is placed in a solution and begins to swell. Which of the following best explains this observation?

Accepted Answer

The solution is hypotonic to the cell, causing water to enter.

Question 19

Which of the following best describes the function of glycoproteins and glycolipids in the plasma membrane?

Accepted Answer

They are involved in cell recognition and are found on the outside of the plasma membrane.

Question 20

Which of the following is true regarding the resting membrane potential of a typical animal cell?

Accepted Answer

It is negative because the inside of the cell is more negative than the extracellular fluid.

Chapter 3: The Cell – Structure and Function in Human Anatomy & Physiology

Guida di studio - Domande di pratica

Study guide - Flashcard