Question

In human body diffusion takes place in which organ?

Answer 1

Lungs......

The lungs possess millions of tiny air sacs that are called alveoli, each of which are in close contact with capillaries. As air is breathed in the alveoli inflate and oxygen diffuses across the alveoli wall and into the capillaries.

Answer 2

in human body, there are two places where diffusion takes place:
lungs: exchange of gases(oxygen and carbon dioxide)
gut: (digested food products) from the gut cavity