gametogenesis of male gametes in flowering plants:
the formation starts from archesporium cells in the immature(forming) anther of the flower.....
male gametes r alos known as the microspores...
first archesporium divides mitotically to form 1-primary sporogeneous layer(towards inside)
2- primary parietal layer(this is towards the outside)
the primary parietal layer divides mitotically to form three layers: epidermis, endothetium, and the inner most tapetum(covering the sporogeneous layer)-the outer layers form the wall of mature anther
the primary sporogeneuos layer may divide mitotically and the cells formed are called microspore mother cells....
then every one such cell divides meiotically to give 4 haploid cells,thse cells are generally arranged in tetraheds(of different orientation)....
when the anther further matures, these tetraheds breAK UP,
thus releasing several single free microspores,these are known as the pollen grains -OR THE MALE GAMETOPHYTE!
note:however sometimes the tetraheds(of 4 microspores) fails to seperate then such ga,etes are called compound pollen grains!
-does it help?!
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