Seed - Dicot Seed Structure

Description:

Outer most covering of a seed is the seed coat. The seed coat is made up of two layers, the outer testa and the inner tegmen.

Seeds show the presence of a scar on the seed coat called hilum. This is the point at which the developing seed is attached to the fruit. Above hilum there is a small pore called micropyle, which is place for the entry of pollen tube into the ovule during the process of fertilization.

Seeds possess embryo, embryonal axis and two cotyledons within the seed coat. Cotyledons are often fleshy and contains reserve food materials.

Presence of radical and plumule at the two ends of the embryonal axis which develop into the root and the shoot respectively.

At times seeds show the formation of endosperm in some seeds like castor as a result of double fertilization, which is a food storing tissue.

In some seeds like bean and gram the endosperm is not present in mature seeds. Such seeds are called non-endospermous seeds.