Suggest why many leaves are very broad and thin?

Explanation:

Due to their broad surface areas, green leaves can absorb more sunlight at a given time, and due to the thinness of the leaves, the light energy can easily penetrate the leaf surface and be trapped by the chloroplasts. This makes photosynthesis efficient. Therefore, green leaves are thin and broad.

Explanation:

Sometimes, it helps in photosynthesis because the leaves being broad and thin increases the excitement of chlorophyll molecules contained in them , further absorbing energy for more energy which is later required to break the OH- ions.