Class 12th Biology 2017 Set2 Delhi Board Paper Solution
In a flowering plant, a microspore mother cell produces four male gametophytes while a megaspore mother cell forms only one female gametophyte. Explain.
In flowering plants, microspore mother cells are found embedded in the sporophytic tissue of anther. These cells undergo meiosis and give rise to four microspores that remain together in a microspore tetrade. After attaining maturity, these microspores separate from each other and each microspore develops into a male gametophyte or pollen grain containing either two cells or three cells. On the other hand, megaspore mother cell develops in the ovary of a flower and divides by meiotic division to produce four megaspores. From these, three degenerate while, the one undergoes further development and mitotic divisions to produce female gametophyte.
Thus, in a flowering plant, a microspore mother cell produces four male gametophytes while, megaspore mother cell produces one female gametophyte.
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