Endosperm Formation in Angiosperms

Nuclear division is the process of cell division in which the nucleus of a cell divides into two or more nuclei. In angiosperms (flowering plants), free nuclear division takes place during endosperm formation. Let's understand this process in detail.

What is Endosperm?

Endosperm is a tissue that is formed inside the seeds of flowering plants. It is triploid (3n) in nature, meaning it has three sets of chromosomes. The endosperm provides nutrition to the developing embryo and is also a source of food for humans and animals.

Process of Endosperm Formation

The process of endosperm formation involves a unique type of nuclear division called free nuclear division or syncytial division. In this process, the nuclear division occurs without cytokinesis (cell division).

The endosperm is formed by the fusion of a sperm cell with two polar nuclei present in the central cell of the female gametophyte. This process is called double fertilization.

After double fertilization, the zygote undergoes several rounds of mitotic division to form the embryo, while the central cell undergoes free nuclear division to form the endosperm.

During free nuclear division, the nucleus of the central cell undergoes repeated rounds of mitosis without cytokinesis, resulting in the formation of a large, multinucleate cell. This cell then undergoes cellularization, which is the process of forming cell walls around the nuclei, resulting in the formation of the endosperm tissue.

Conclusion

In conclusion, free nuclear division in angiosperms takes place during endosperm formation. This process involves the fusion of a sperm cell with two polar nuclei, followed by repeated rounds of nuclear division without cytokinesis, resulting in the formation of a multinucleate cell. The endosperm tissue is then formed by the cellularization of this cell.