The seed in a plant is the part that develops from the ovules after fertilization. They are enclosed in the fruit which develops from the fertilized ovary. The seeds are formed as a result of sexual reproduction and contain the young embryo which can develop into a new plant. Let’s learn more.
Structure of a Seed
Seeds of different plants may vary in many ways, but the basic anatomy remains the same. A typical seed consists of the following parts:
Tesla: It is the outer coat of the seed that protects the embryonic plant.
Micropyle: It is a tiny pore in the testa that lies on the opposite of the tip of the radicle. It permits water to enter the embryo before active germination.
Hilum: Is a scar left by the stalk which attached the ovule to the ovary wall before it became a seed.
Cotyledon: In some plants, this contains high quantities of starch and will provide a source of food for the developing embryo prior to germination, in other plants this role is performed by an endosperm. In monocotyledons, there is just one cotyledon whereas in dicotyledons there are two. Depending on the type of germination (epigeous or hypogeous) the cotyledons may remain below ground or be pulled above ground.
Radicle: This is the embryonic root which will develop into the primary root of the plant. It is usually the first part of the embryo to push its way out of the seed during germination.
Plumule: This is the embryonic shoot. It appears as a bud which will give rise to the shoot and the remaining structures in the plant.
Endosperm: In many plants, a separate part for storage of starch develops and this is called the endosperm. It is seen in maize and wheat.