Layers of a leaf

• upper epidermis


  a transparent layer that light passes through. the cells do not have chloroplasts so they don’t photosynthesise.

  The cells are tightly packed together to protect the leaf
• Palisade layer


  the main photosynthetic layer. The cells are packed with chloroplasts so that they can absorb as much light as possible
• Spongy layer


  the cells also have SOME chloroplasts that absorb any light that passes through the palisade layer. There are large spaces between the cells so that gases can easily pass to and from the palisade cells
• Lower Epidermis


  Protects the underside of the leaf. The only cells of the epidermis that have chloroplasts (can photosynthesise) are the guard cells.
• Guard Cells


  Pairs of specialised cells that have a hole called a stoma between them. Controls the size of the stoma. CO2 moves into the leaf and O2 moves out of the leaf through the stomata.