The palisade cells are the main site of photosynthesis, as they have many more chloroplasts than spongy mesophylls, and also have several adaptions to maximise photosynthetic efficiency; Large Vacuole - Restricts chloroplasts to a layer near the outside of the cell where they can be reached by light more easily.
What is the function of Palisade tissue?
Below the upper epidermis is the palisade layer. This is one or a few layers of cylindrical cells that contain many chloroplasts. Chloroplasts are an important part of plant cells because they are cell structures that allow for photosynthesis.
Why is it good for a leaf to be thin?
Its main functions are photosynthesis and gas exchange. A leaf is often flat, so it absorbs the most light, and thin, so that the sunlight can get to the chloroplasts in the cells. Most leaves have stomata, which open and close. They regulate carbon dioxide, oxygen, and water vapour exchange with the atmosphere.