Exchange And Transport Systems: - Gas Exchange In Plants

- Gas Exchange in plants - 

Gas exchange is able to occur in plants due to their adaptations.

These adaptations would include - 

Thin = Short diffusion pathway// Carbon dioxide and oxygen can pass in and out of the plant cell. 

Large surface area = this would allow for an effective gas exchange because its able to occur over a larger area. 

Air spaces between the spongy mesophyll = allows a diffusion gradient to be maintained 

Guard cells = controls the amount of Carbon dioxide and oxygen diffuses in and out of the cell. 

For a most gaseous exchange to occur:
- There are many small pores // stomata // no cell is far from a stoma // short diffusion path.
- Numerous interconnecting air-spaces occur throughout the mesophyll
- Large surface area of mesophyll cells // rapid diffusion

Stomata:

Each stoma is surrounded by pair of special guard cells which open and closes the stomata pores // controls the rate of gaseous exchange // plants evolved to balance the conflict between gas exchange and controlling the water loss in the plant.