Parts of Leaf

A typical leaf has three parts:

1. Leaf base
2. Petiole
3. Lamina or leaf blade

Leaf base

Lower most part of leaf by which it is attached to the stem node. It may be expanded as sheath (in monocots) or bear lateral outgrowths (stipules) as in dicots.

Petiole

It is the stalk of leaf. Leaf can be petiolate (with petiole) as in many dicots or sessile (without petiole) as in most monocots. Petiole may get modified and swell (e.g. water hyacinth) or develop wings (e.g. orange) or become flat like a leaf (e.g. Australian Acacia).

Lamina or leaf blade

It is a green, thin, flattened and expanded part of leaf with veins and veinlets traversing through its surface. The most prominent vein running from base to apex and present in the middle of leaf blade is called mid rib. Veins provide support and conduct water, minerals and prepared food.