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Parts of a leaf
A leaf has three main parts:
The Base: This is the joining point of the leaf to the stem.

The stalk or Pe ole: The pe ole is the connec on of the stem to the blade. It can be
short or long. It is generally cylindrical or semi-circular in shape.

The Lemna or Leaf Blade: Blade is the expended part of the leaf. Food making process
occurs in the blade. Leaf blade has a mid vein or midrib and many side veins. Veins
carry food and water in leaf. They also support the blade, much as the metal ribs
support the fabric of umbrella.

parts of leaf stomata on leaf

The outer surface of the leaf has many ny pores. These openings are called stomata.
These stomata enable carbon dioxide to enter the leaf. A leaf has many stomata.
However, the pores are so small that they make less than 1 percent of the leaf's
surface.

Func ons of a Leaf
A leaf performs the following func ons:
1. Photosynthesis: The primary func on of the leaves is to manufacture food by the
process of photosynthesis. The leaves contain a green pigment called chlorophyll.
2. Interchange of Gases: Leaves have numerous ny openings called stomata.
Through these minute pores exchange of oxygen and carbon dioxide occurs during
photosynthesis and respira on.
3. Evapora on of Water: The excess water present in the plant evaporates through
stomata on the leaves. This process is called transpira on.

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