Biology

Types of Leaves

A leaf is said to be simple, when its lamina is entire or when incised, the incisions do not touch the midrib. When the incisions of the lamina reach up to the midrib breaking it into a number of leaflets, the leaf is called compound. A bud is present in the axil of petiole in both simple and compound leaves, but not in the axil of leaflets of the compound leaf.

The compound leaves may be of two types (Figure). In a pinnately compound leaf a number of leaflets are present on a common axis, the molds, which represents the midrib of the leaf as in neem.

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Fig: (a) pinnately compound leaf, (b) palmately compound leaf

In palmately compound leaves, the leaflets are attached at a common point. i.e. at the tip of petiole, as in silk cotton.