Question

explain structure of pollen grain

Answer 1

The pollen grain consist inside of the grain contains cytoplasm along with the tube cell (which becomes the pollen tube) and the generative cell (which releases the sperm nuclei). The outer shell is made of two layers. The inner layer is called the intine, and is made of cellulose.

Answer 2

pollen grains are attached to the tip of stamen which is the male reproductive part of the hibiscus flower.