How does the development of male gametophyte or pollen take place ?

Explanation

The haploid microspore (pollen ) is the pioneer structure of the male gametophyte . It begins to germinate before it is shed . Microspore nucleus at the time of germination move to the place adjacent of spore wall . It then divides into two cells one larger cell called vegetative cell and smaller cell called generative cell . The latter is variable in form and has denser cytoplasm . The exine ruptures near germ pore and a delicate tubular structure is formed called pollen tube and tube nucleus shifts into it. Meanwhile generative cell divides into two male gametes .