Diffusion is the movement of particles from an area of high density to an area of low density. In this way gasses will move from an area dense with gas to an area of low density.
In the circulatory system oxygen enters the blood and carbon dioxide leaves the blood via gaseous exchange. Gasses move across the walls of alveoli to an area of lower density than they are in: Oxygen moves into the blood as there is a low density of oxygen in the blood; Carbon dioxide moves into the lungs as it is an area of lower density.
Thank you :)
ReplyDeleteisn't it talking about gas exchange in plants not humans?
ReplyDeleteHumans :) as it is part of the gaseous exchange topic that talks about the chest cavity etc.
DeleteHumans :) as it is part of the gaseous exchange topic that talks about the chest cavity etc.
Deleteyes! thats what i came here to look for :D
ReplyDeleteNo I think it is asking about plants
ReplyDeleteThis question is asking for both plants and animals
ReplyDeleteguys its both plants and animals - its just the general role of diffusion in gas exchange :)
ReplyDeletemore can be found here
ReplyDeletehttp://igcse-biology-notes.blogspot.hk/2017/06/238-understand-role-of-diffusion-in-gas.html
Btw for anyone reading this it is more correct to say "lower concentration" instead of "lower density" it could cost you a mark on an exam. :)
ReplyDelete