What Is The Structure Of Seed?

A seed consists essentially of a seed coat and a young plant, the embryo. The seed coat may be made of inner tegmen and outer testa. On the seed coat, a hilum, the scar which indicates the place of attachment of a seed in the fruit is present. At one end of hilum is the micropyle. It is through the micropyle that seed absorbs water during the process of germination. The embryo consists of epicotyl, one or two seed leaves, the cotyledons, and hypocotyls. The portion of the embryo above the point of attachment of cotyledons to embryo axis, and below the plumule is called epicotyl. The plumule forms shoot. The portion of the embryo below the point of attachment of cotyledons to embryo axis but above the radicle, is hypocotyls.


The seed also contains food, derived from the endosperm tissue. The food may remain as such or may be digested and stored in the cotyledons. Thus the cotyledons become thick due to presence of food. The food is supplied to developing plant during the process of germination of seed. In the grain of maize, the cotyledon is modified into an organ called scutellum, a term that comes from the Latin word meaning shield.