Question 1

Which of the following best describes the amphipathic nature of phospholipids in the plasma membrane?

Accepted Answer

They have both hydrophilic and hydrophobic regions.

Question 2

What is the primary function of cholesterol in the plasma membrane?

Accepted Answer

It provides strength and stability to the membrane.

Question 3

Which type of membrane protein is most likely to function as a channel for ions such as Cl$^-$?

Accepted Answer

Integral (transmembrane) protein

Question 4

A red blood cell is placed in a hypertonic solution. What will happen to the cell?

Accepted Answer

It will lose water and shrink.

Question 5

Which process requires energy in the form of ATP to move molecules against their concentration gradient?

Accepted Answer

Active transport

Question 6

The sodium-potassium pump (Na$^+$, K$^+$ ATPase) is an example of:

Accepted Answer

Active transport

Question 7

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

Accepted Answer

Cell recognition and identification

Question 8

Which of the following statements about facilitated diffusion is correct?

Accepted Answer

It moves substances down their concentration gradient without using ATP.

Question 9

Refer to the first image. Which process is illustrated, and what is its main function?

Accepted Answer

Endocytosis; bringing large particles into the cell via vesicle formation

Question 10

Refer to the second image. Which process is responsible for the secretion of neurotransmitters from nerve cells?

Accepted Answer

Exocytosis

Question 11

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

Accepted Answer

Synthesis of DNA

Question 12

A plant cell is placed in a hypotonic solution. What is the expected outcome?

Accepted Answer

The cell will gain water, but the cell wall prevents bursting.

Question 13

Which type of endocytosis is highly specific and involves the binding of molecules to receptors on the cell surface?

Accepted Answer

Receptor-mediated endocytosis

Question 14

Which of the following best explains why ions such as Na$^+$ and K$^+$ cannot freely cross the plasma membrane?

Accepted Answer

They are charged and require transport proteins to cross the hydrophobic core.

Question 15

Which equation best represents the movement of water during osmosis?

Accepted Answer

$\Delta \Psi = \Psi_s + \Psi_p$

Question 16

A cell uses ATP to move glucose into the cell against its concentration gradient. Which process is this?

Accepted Answer

Active transport

Question 17

Which of the following is a real-life example of phagocytosis?

Accepted Answer

A white blood cell engulfing a bacterium

Question 18

Which of the following statements about membrane carbohydrates is correct?

Accepted Answer

They play a key role in cell recognition and immune response.

Question 19

Which of the following best describes the difference between channel and carrier proteins?

Accepted Answer

Channel proteins form pores for molecules to pass through, while carrier proteins change shape to move molecules.

Question 20

Which process is used by cells to export large molecules, such as hormones, out of the cell?

Accepted Answer

Exocytosis

Membrane Structure and Function: Study Notes

Study Guide - Practice Questions