With the help of a suitable labelled diagram, describe the structure of a dicot seed.

Taking Bean seed as an example of a dicot seed, below is its labelled diagram:

The structure of a bean seed is described below:

1. The bean seed is protected by a thin, greenish outermost covering called seed coat. It protects the seed from insects and bacteria as well as from mechanical injury.
2. The seed coat is divided into two parts, the outer part is called Testa and inner part is called Tegmen. Tegmen is a thin membrane that lies under the Testa.
3. On the inner concave side of the seed, there is a scar called Hilum which marks the place where the seed was attached to the fruit wall.
4. Above the hilum is a small pore called Micropyle. The Micropyle absorbs and allows the entry of as much water as is required for germination.
5. On removing the testa and tegmen from a soaked bean seed, the seed is made up of two fleshy seed leaves called the Cotyledons. They contain stored food material which is used by the seedling for growth.
6. In between the two cotyledons is located the delicate embryo which consist of a Radicle and Plumule. The radical develops into a root, while the plumule develops into a shoot.