B2 Cell Transport

Diffusion

Definition- The spreading of particles from a higher concentration to a lower concentration

Movement of particles- Particles move down the concentration gradient from high concentration to low concentraion

Energy required?- No its a passive progress

Diffusion in Humans- Nutrients in small intestine through capillaries into the villi. Oxygen diffuses from the air in to the alveoli into the blood.

Diffusion in Fish- Oxygen from water passes over the gills and diffuses into the blood

Diffusion in Plants- Carbon dioxide used for photsynthesis diffuses into leaves through the stomata

Factors that affect the rate of diffusion- Difference in concentration, tempertaure and surface are of the membrane

Osmosis

Definition- The diffusion of water from a dilute solution to concentrated solution through a permeable mebrane

Movement of particles- Water moves from lower solute…