Describe the internal structure of anther (diagram is not expecte…

Question

Describe the internal structure of anther (diagram is not expected).

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Answer

Anther wall:
Parietal cell undergoes divisions to form anther wall layers. The anther wall is divided into four layers as follows:

Epidermis:
It is the outermost protective layer made up of tabular (flattened) cells.
Endothecium:
It is a sub-epidermal layer made up of radially elongated cells with fibrous thickenings.
Middle layers:
Inner to endothecium is middle layer made up of thin-walled cells (1-2 layered), which may disintegrate in mature anther.
Tapetum:
It is the inner most nutritive layer of anther wall. It immediately encloses the sporogenous tissue (microspore mother cells).
The sporogenous tissue is composed of many diploid microspore mother cells (Pollen mother cells). These microspore mother cells in the microsporangia undergo meiosis, each becoming four microspores. The microspores divide by mitosis to produce pollen grains.

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