- The cells in the spongy mesophyll (lower layer) are loosely packed, which increases the surface area of the leaf, allowing for more carbon dioxide to be absorbed
- Guard cells (stomata) on the lower part of the leaf controls the diffusion of gases in to the leaf.
- Leaves are thin, making it easier and quicker for gas to diffuse quickly through it.
Let me explain how the stomata work:
- During the day, the guard cells are absorbing water (via osmosis), which makes them turgid, opening the stoma and therefore allowing gas into the plant
- At nighttime the opposite happens. The guard cells lose water, becoming flaccid and closing the stoma.
