Question

Explain in details the process of development of male gametophyte

Answer 1

Answer:

x-chromosomes and y-chromosomes

Answer 2

Answer

• The group of four pollen grain is called tetrad.

• Latter the mature pollen grain separate from the tetrad.

• A mature pollen grain has a two layered wall the outer called exine.

• Exine is thick as well as spinous outgrowth.

• It is made up of a complex substance called sporopollenin.

• It is resistant to decay and hence the pollen grains are seen well preserved in fossils.

• At certain places the exine is absent or is very thin giving an appearance of a pore called germ pores.

• There are three germ pores in dicots.

• There is only one germ pore in monocots.

• The inner is thin and smooth, so it is known as intine.

• Intine is made up of cellulose