Describe internal structure of microsporangium

Explanation

A typical microsporangium appears near circular in outline
It is generally surrounded by four wall layers. They are epidermis, endothecium, middle layers and the tapetum
The outer three wall layers perform the function of protection and help in dehiscence of anther to release the pollen.
The innermost wall layer is the tapetum. It nourishes the developing pollen grains. Cells of the tapetum possess dense cytoplasm and generally have more than one nucleus
Tapetum secretes enzyme and hormone both and special protein. It decides correspondence of pollen grain
The cells of epidermis are stretched or scattered or flat

(a) Transverse section of a young anther (b) Enlarged view of one microsporangium showing wall layers (c ) A mature dehisced anther.
Endothecium is fibroius layer