Q.With well labelled diagram, describe various parts of a typical leaf.

A typical leaf consists of three main parts — the leaf base, the petiole, and the lamina (leaf blade) — with the lamina showing veins and venation patterns that supply and support it.

A leaf is a lateral, generally flattened structure borne on the stem, developing at a node and usually bearing an axillary bud in its axil. It develops acropetally and is one of the most important vegetative organs, being the principal site of photosynthesis. A typical dorsiventral (dicot) leaf has the following parts:

1. Leaf base: the part attaching the leaf to the stem. In some plants (e.g. legumes) it becomes swollen, called the pulvinus. In monocots, the leaf base is often expanded, forming a sheath partly or wholly covering the stem. Small leaf-like structures called stipules are sometimes present at the leaf base.
2. Petiole: the stalk of the leaf, which holds the blade out to the light and allows it to flutter in the wind, thereby helping to cool the leaf and bring fresh air to the leaf surface. …