Hello, microsporogenezis occurs inside the pollen sac of the anther and is due to formation of haploid microspore forming from the diploid microspore mother cell while megasporogenesis occurs in ovary and is due to haploid megaspore forming from the diploid megaspore mother cell. In both cases meiotic division happens and a pollen may be an outcome in microsporogenezis but megaspore will be the outcome of megasporogenesis.

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