In a microspore mother cell four male gametophyte are produced,while in a megaspore mother cell only 1 female gametophyte is produced .explain?

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​Please find below the solution to the asked query        

As development occurs in the anther, the sporogenous tissue undergoes meiosis to form microspore tetrad. Each cell of sporogenous tissue has capacity to give rise to a tetrad. Each cell is a potential pollen or PMC. As the anther matures, the microspores get detached from each other and develop into pollen grains. Since, all four microspores are functional in microspore mother cell, four male gametophytes are formed.

The megaspore mother cell   (MMC) gets converted into megaspores by the process of megasporogenesis. The MMC is large and contains a dense cytoplasm and a prominent nucleus. It undergoes meiosis to produce four  megaspores. In most flowering plants, only one megaspore is functional while the other three degenerate. The single functional megaspore develops into the female gametophyte. 

Hope this information will clear your doubts about the topic.    Regards