STRUCTURE OF A LEAF
Upper Epidermis: it is a layer of cells that cover the leaf and protect it, it is covered by a layer of wax called cuticle.
Mesophyll Layer:
Mesophyll Layer:
- Palisade Mesophyll: a layer of palisade cells which carry out most of photosynthesis
- Spongy Mesophyll: a layer of spongy cells beneath the palisade layer, they carry out photosynthesis and store nutrients.
Lower Epidermis: similar to the upper epidermis, only that it contains a special type of cells called guard cells. Guard cells are a specialised type of cells that control the passage of carbon dioxide into the cell and the passage of oxygen out of the cell by opening and closing the stomata (a hole in the leaf through which gases pass) so guard cells are responsible for the gas exchange
|