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Leaves are known as the major sites for the process of food synthesis which is otherwise known as photosynthesis. In the leaf cells, the presence of chlorophyll pigment makes most leaves usually green. However, some leaves may possess different colors due to other pigments that mask chlorophyll.

Leaf structures and forms vary in different plants. Monocot and dicot leaves can be differentiated by the venation patterns of the leaves. These are mainly two types; Parallel venation and reticulate venation.

• Leaves having parallel venation are found in monocot plants. The pattern of parallel venation is like the straight lines of veins running across the length of the leaf. A good example isTulipa.

• Leaves having reticulate venation are mainly found in dicot plants. The pattern of veins forms a net-like appearance on the leaf surface diverging in many directions (branching pattern). One good example is Ginkgo biloba.