MICROSPORANGIUM AND MICROSPOROGENESIS

 Microsporangium and Microsporogenesis: - Male reproductive parts of a flower is called  Androecium. Parts of androecium are called stamens. A stamen generally has two parts anther and filament. If we make a transverse section through the anther we find it has four lobes each lobe has a sac like structure called pollen sac. Pollen sac contains in it pollen grains. 

Pollen sac are known by another name called Microsporangium. Externally the microsporangium is covered by a layer called Epidermis.Below the epidermis there is the occurance of Hypodermis. One of the hypodermal cell become very prominent with bigger cell, dense cytoplasm and is called as Archesporial cell.

Archesporial cell.undergo division to form two cells called Primary parietal cell and Primary sporogeneous cell.

Cells that are formed from the archesporial cell undergo anticlinial and periclinal division.

Due to this division of the Primary parital cell forms Endothecium, Middle layer and Tapetum.  Primary sporogeneous cell.leads to the formation of sporogenous tissue.

So total layers that are formed are  - Epidermis, Endothecium, Middle layer , Tapetum.  and the sporogenous tissue. 

All of these layers have a distinct role to play in the process of  microsporogenesis.

Sporogenous tissue which is formed of Primary sporogenous cell plays an important role in the formation of spore. One of the cell of the sporogenous tissue develops bigger and denser than  that rest and is known as MMC ie. Microspore mother cell.The cell undergo meiosis to form four cells and forms Microspores,

         

         

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