B2.1.2

Question 1

Dissolved substances can move into and out of cells by

Answer 1

Diffusion

Question 2

Diffusion is …

Answer 2

The spreading of the particles of a gas of of any substance in solution, resulting in a net movement from a region where they are of a higher concentration to a region with a lower concentration. The greater the difference in concentration, the faster the rate of diffusion.

Question 3

Oxygen required for respiration passes through cell membranes by

Answer 3

Diffusion