Movement of Substances In and Out of Cells

?
  • Created by: rq5253
  • Created on: 26-12-15 17:59

Diffusion:

Definition: The net movement of substances from an area of high concentration to an area of low concentration, down a concentration gradient, through a partially permiable membrane.

Example: The spread of air freshener through a room.

Factors which will make diffusion faster:

  • Shorter distance to travel
  • Greater concentration
  • Larger surface area
1 of 3

Osmosis

Definition: The movement of substances from an area of high concentration of water to an area of low concentration of water, down a concentration gradient, through a partially permeable membrane.

Example: The spread of salt molecules in water or red blood cells inside the body.

2 of 3

Active Transport

Definition: The movement of substances from an area of low concentration to an area of high concentration, up a concentraion gradient, through a partially permeable membrane. Active Transport requires a protein carrier to transport molecules and also requires energy from respiration.

Example: The root hair cells in plants roots aborbing mineral ions from the soil.

3 of 3

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Exchange of materials resources »