A female gametophyte is a haploid cell that develops from the megagametophyte in a plant ovule. It contains the genetic material necessary for the development of a new plant.

The male gametophyte, which is also a haploid, develops from the pollen grain and contains the genetic material necessary for the development of a new plant.

When the pollen grain germinates, the male gametophyte grows out and releases sperm cells that fertilize the female gametophyte.

7-celled, 8 nucleate nature of female gametophyte

The 7-celled, 8 nucleate nature of female gametophyte is due to the presence of an extra nucleus in the central cell.

The central cell has two nuclei and each of the three antipodal cells, 1 egg cell, 2 synergids have one nucleus each.

So, in total, there are 8 nuclei inside a female gametophyte.

Shape and Structure

In angiosperms, the female gametophyte is generally small and inconspicuous. It is enclosed within the protective coat of the ovule and is usually not visible without a microscope.

The shape and structure of a female gametophyte in angiosperms are not as well-defined as in other groups of plants.

There is a great deal of variation among species, and even within a single species, there can be considerable differences.

Parts of the female gametophyte

• There are two ends – Chalazal End and Micropylar End. The Chalazal End is the point where the ovule was attached to the plant before it was pollinated.The Micropylar End is the point where the pollen tube enters the ovule
• The female gametophyte typically contains a large central cell and several smaller peripheral cells.
• The central cell divides by mitosis to produce the egg cell and the two polar cells. The peripheral cells may also divide to form additional egg cells or polar cells
• The synergids are two cells that are adjacent to the egg cell. They play a role in guiding the pollen tube to the egg cell
• The antipodals are 3 cells located at the opposite end of the gametophyte from the egg cell. They are responsible for nourishing the embryo after fertilization
• The filiform apparatus is a structure that surrounds the egg cell and helps to guide the pollen tube to it.

Total number of cells present

So, in total, a female gametophyte has 7 cells. They are –

• 1 central cell
• 3 Antipodal Cells
• 2 synergids
• 1 Egg Cell

And so, female gametophyte in angiosperms is said to have a 7-celled nature. The 8 nucleate nature is due to the extra nucleus in the central cell.

Summary

The central cell in a female gametophyte has two nuclei and each of the three antipodal cells, two synergids, one egg cell has one nucleus each. So, in total, there are 8 nuclei inside a female gametophyte making it have a 7-celled and 8 nucleate nature.

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