BIO Movement of substances

Diffusion

Movement of particles from a region of higher concentration to a region of lower concentration until they reach equilibrium

Diffusion in animals happens at…

Small intestine, capillaries,digestive system

Diffusion in plants happen at…

Stomata

Substances a cell needs

Oxygen, Glucose for respiration

Substances a cell need to get rid of

co2, urea (so they don’t build up in the cell)

Equilibrium

Equal concentration everywhere

Osmosis

Movement of water molecules, a special type of diffusion, from a high concentration of water to a low concentration of water, occurs at a semi-permeable membrane

Concentrated

Low water potential

Most concentrated

Lowest water potential

Dilute

Higher water potential

If cells are placed in concentrated salt solution

They shrink

If cells are placed in distilled water

Cells swell and burst