[Biology Class Notes] on Seed Formation Pdf for Exam

The seed is the part of a plant that grows from the ovules after fertilisation. They’re contained within the fruit that grows from the fertilised ovary. 

Sexual reproduction produces seeds, which contain a young embryo capable of growing into a new plant.

Structure of a Seed

Although the anatomy of seeds from different plants may differ in many ways, the underlying anatomy remains the same. The following are the components of a typical seed:

This is the seed’s outer coat that serves as a protective barrier for the developing plant inside.

It’s a little pore in the testa that’s located on the opposite side of the radical’s tip. Before active germination, it allows water to enter the embryo.

A hilum is a scar created by the stalk that connected the ovule to the ovary wall before it became a seed.

This includes a lot of starch and serves as a food supply for the developing embryo before germination in some plants; in other plants, and endosperm serves in this role. There is just one cotyledon in monocotyledons, but there are two in dicotyledons. 

The cotyledons may remain underground or be dragged above the earth, depending on the kind of germination (epigeous or hypogeous).

The embryonic root will eventually develop into the plant’s major root. During germination, it is usually the first component of the embryo to emerge from the seed.

The embryonic shoot is known as a plumule. It appears as a bud that will give rise to the shoot and the rest of the plant’s structures.

In many plants, a distinct component called the endosperm develops for starch storage. It can be found in both maize and wheat.

Function of Seed

The following functions are carried out by the seeds:

• They aid in the germination of new plants.

• Food reservoirs in the form of cotyledons and endosperm are found in the seeds.

• The embryo inside is protected by the seed coat, which is protective.

Importance

• The embryo plant is protected by seeds, which allows it to develop once it finds adequate soil.

• Seeds are a protective structure that allows a plant embryo to live for a long time before germinating. 

• Until the embryo’s growing conditions are favourable, the seed can remain dormant.

• To address the needs of embryos in their early stages of development, food sources for plant embryos are pre-packaged in seeds.

• Creatures, wind, birds, and other animals may quickly transport seeds, allowing the plant to populate a broad region. The wind can carry some of them anywhere.

• Seeds can survive without water, thus the plant can survive if there is a drought.

• Seeds are produced in vast quantities so that plants can reproduce.