Male Gametophyte or Microsporogenesis
Stamens are reproductive organs in flowering plants and are known as microsporophyll. Each anther of four pollen sacs called micro sporangia.
It consists of outer wall, a single layer of nutritive cells called tapetur and central mass of pollen mother cells (PMC) or microsporocyte with 2n chromosome compliment. Each pollen mother cell undergoes meiosis and give rise to four microspores or pollen grains, consisting of haploid (n) chromosome compliment. This is known as microsporogenesis.
Each pollen grain (Microspore) consists of two coats called exine and intine. The nucleus of pollen grain divides mitotically and gives rise to two nuclei called tube nucleus and generative nucleus. The generative nucleus divides mitotically and produces two sperm nuclei called male gametes.