Diffusion - random mixing and intermingling of particles, move high concentration → low concentration till equilibrium

Concentration gradient - Difference between the concentration of molecules in 2 areas

How substances move in and out of the cells

Passive - Diffusion and Osmosis

• no energy
• high to low concentration
• down concentration gradient

Active -

• needs energy
• low to high concentration
• against concentration gradient

Factors That Affect Diffusion -

1. Distance Needed To Travel - Lesser the distance, faster the diffusion
2. Concentration Gradient - Greater the difference in concentration, faster the diffusion
3. Density Of Diffusion Particles - Low density means faster movement = faster diffusion
4. Temperature - Obvious
5. Surface area - More diffusion molecules per second.

Examples Of Diffusion In Body-