Question 1

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

Accepted Answer

A flexible layer of phospholipids with proteins embedded and able to move laterally.

Question 2

A red blood cell is placed in a 10% NaCl solution. What will happen to the cell, and why?

Accepted Answer

It will shrink because water moves out toward the higher solute concentration.

Question 3

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

Accepted Answer

Cell recognition and signaling.

Question 4

Why are phospholipids arranged as a bilayer in water?

Accepted Answer

Hydrophilic heads face water, and hydrophobic tails face each other.

Question 5

Which equation best represents the rate of diffusion according to Fick's Law?

Accepted Answer

$$J = -D \frac{dC}{dx}$$

Question 6

In the dialysis tubing experiment, why did the bag containing a sugar solution gain weight?

Accepted Answer

Water moved into the bag by osmosis because the solute concentration was higher inside.

Question 7

Which of the following best explains why IV fluids must be isotonic to blood?

Accepted Answer

To ensure that red blood cells do not burst or shrivel due to osmotic imbalances.

Question 8

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

Accepted Answer

DNA replication.

Question 9

What is the main difference between simple diffusion and facilitated diffusion?

Accepted Answer

Facilitated diffusion requires a protein channel or carrier, while simple diffusion does not.

Question 10

A plant cell is placed in a hypertonic solution. What is the expected observation and why?

Accepted Answer

The cytoplasm will pull away from the cell wall (plasmolysis) as water leaves.

Question 11

Which of the following factors would NOT increase the rate of diffusion across a membrane?

Accepted Answer

Decreasing the concentration gradient.

Question 12

Which of the following best defines osmosis?

Accepted Answer

The movement of water across a selectively permeable membrane from high to low water concentration.

Question 13

Which type of membrane transport is used by glucose to enter most cells?

Accepted Answer

Facilitated diffusion via carrier proteins

Question 14

What is the role of cholesterol in the plasma membrane?

Accepted Answer

It stabilizes membrane fluidity and structure.

Question 15

Which tissue type is characterized by striations, branching, and intercalated discs?

Accepted Answer

Cardiac muscle

Question 16

Which of the following best describes selective permeability?

Accepted Answer

The membrane allows some substances to pass while restricting others.

Question 17

Which of the following statements about aquaporins is correct?

Accepted Answer

They are water channel proteins that speed up osmosis.

Question 18

A patient receives an IV of pure water by mistake. What is the most likely outcome for their red blood cells, and why?

Accepted Answer

Cells will swell and burst because water enters by osmosis.

Question 19

Which tissue type is specialized for rapid communication and impulse conduction?

Accepted Answer

Nervous tissue

Question 20

Which of the following best explains why plant cells do not burst in hypotonic solutions, but animal cells do?

Accepted Answer

Plant cells have a rigid cell wall that prevents bursting.

Cell Membrane Structure, Diffusion & Osmosis, and Histology Study Guide

Study Guide - Practice Questions