DIFFUSION

Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration. 

Examples in our body:

1) In our lungs:

  • Oxygen from alveoli to blood vessels
  • Carbon dioxide from blood vessels to alveoli

2) In our tissues:

  • Oxygen from capillaries to respiring cells
  • Carbon dioxide from respiring cells to capillaries
  • Glucose from capillaries to respiring cells

OSMOSIS

Osmosis is the movement of water molecules from a region of higher concentration to a region of lower concentration through a partially permeable membrane.

Osmosis occurs wherever there is movement of water molecules in our body.