$$ \text{Net movement} = \text{from low solute concentration to high solute concentration} $$

Question 1

Which of the following best describes diffusion in biological systems?

Accepted Answer

The random movement of molecules down their concentration gradient until equilibrium is reached.

Question 2

A cell is placed in a hypotonic solution. What is the most likely outcome for the cell?

Accepted Answer

The cell will gain water and swell, possibly bursting.

Question 3

Which equation best represents the net movement of water during osmosis?

Accepted Answer

$$ 	ext{Net movement} = 	ext{from low solute concentration to high solute concentration} $$

Question 4

Which of the following is TRUE about a semi-permeable membrane?

Accepted Answer

It allows certain molecules to cross while restricting others.

Question 5

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 6

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

Accepted Answer

Plant cells have a rigid cell wall that prevents excessive expansion.

Question 7

Which scenario best illustrates equilibrium in the context of diffusion?

Accepted Answer

Molecules continue to move, but there is no net change in concentration across the membrane.

Question 8

If a cell is placed in an isotonic solution, what will happen to its size?

Accepted Answer

It will remain the same size.

Question 9

Which of the following is NOT a property of osmosis?

Accepted Answer

It requires energy input from the cell.

Question 10

A student observes that when salt is added to the outside of a plant cell, the cell shrinks. What type of solution was the cell placed in?

Accepted Answer

Hypertonic

Question 11

Which of the following best describes the concentration gradient?

Accepted Answer

A difference in the concentration of a substance across a space or membrane.

Question 12

Which process is responsible for the movement of oxygen from the lungs into the blood?

Accepted Answer

Diffusion

Question 13

A cell with a plasma membrane is placed in a solution and its size increases. What can you infer about the solution?

Accepted Answer

It is hypotonic to the cell.

Question 14

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

Accepted Answer

Water moving from the soil into plant roots.

Question 15

Which formula can be used to calculate the rate of diffusion?

Accepted Answer

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

Question 16

Which of the following statements about active transport is correct?

Accepted Answer

It requires energy, usually in the form of ATP.

Question 17

A cell is placed in a solution and water moves out of the cell. What type of solution is this?

Accepted Answer

Hypertonic

Question 18

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

Accepted Answer

Animal cells lack a cell wall to resist the influx of water.

Question 19

Which of the following is an example of a semi-permeable membrane in living organisms?

Accepted Answer

Plasma membrane of a cell

Question 20

If a cell is placed in a solution and there is no net movement of water, what can you conclude about the solution?

Accepted Answer

It is isotonic to the cell.

Membrane Transport: Diffusion, Osmosis, and Tonicity

Study Guide - Practice Questions