Biology

Diffusion is the net movement of particles from an area of high concentration to an area of low concentration across a concentration gradient.

Diffusion is animals tend to happen across a semi permiable membrane.

In the human body key areas for diffusion are:

• across the avoli in the lungs (oxygen and carbon dioxide)
• across the placents from mother to baby (oxygen and nutrients) and from baby to mother (carbon dioxide and other waste products)
• across the small intestine into the blood stream (nutrients from digestion inc glucose)

The rate of diffusion is increased by adaptations such as:

• thin surface membrane
• large surface area
• large difference in concentration gradient