Q6 of 26 Page 1

State any two characteristics of the tapetum, present in the microsporangium of an angiosperm. Why are non-viable pollen grains seen to develop in a microsporangium where tapetum is damaged or under developed? Give a reason.

The microsporangium has for protection walls and the innermost of these wall layers is tapetum.


Characteristics of the tapetum –


• It nourishes the developing pollen grains.


• Cells of tapetum have a dense cytoplasm and more than one nucleus.


Non-viable pollen grains are seen to develop in a microsporangium where tapetum is damaged or under developed because a damaged or under-developed won’t provide proper nourishment to the developing pollen grains.


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