A seed is a ripened ovule. At the time of separation from the parent plant it consists of an embryo and stored food supply, both of which are encased in a protective covering.

The activation of the metabolic machinery of the embryo leading to emergence of a new seedling plant is known as germination.

Photos of a seed and a cross section of a seed shown. The seed coat, cotyledons, endosperm, and radicle are identified.