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Question
Describe the structure of its microsporangium.
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Solution
A microsporangium is a cylindrical sac which appears circular in the transverse section. It contains the following parts:
(1) Outer wall
(2) Central homogeneous sporogenous tissue
(3) Epidermis
(4) Endothecium
(5) 1–3 middle layers and tapetum
The outer three layers perform the function of protection in the younger anther andthe mechanism of dehiscence in the ripe anther.The endothecial cells develop fibrous thickening of α-cellulose on the inner and radial walls and die. The innermost layer is called the tapetum. It nourishes the developing pollen grain.
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