Question

Which of the following is not true about microsporogenesis and megasporogenesis?

I) All the cells in the microspore and megaspore tetrad give rise to microspores and megaspores respectively.
II) Both the processes involve meiotic division.
III) One of them occurs in the ovule and the other occurs in the megasporangium.
IV) One of them results in the formation of mature embryo sac and the other results in the formation of pollen grains.

• A. Only I and III are not true
• B. Only III is not true
• C. I, III & IV are not true
• D. I and II are not true

Answer 1

The correct option is C I, III & IV are not true

First statement is not true because all the cells of microspore tetrad only give rise to microspores.
In case of megaspore tetrad, three of the four cells disintegrate and only one of them matures into a megaspore.
Microspores are the precursors of the pollen grains and megaspores are the precursors of the mature embryo sac.

Second statement is true.

Third statement is not true because both ovule and megasporangium are same. Megasporogenesis occurs inside the ovule while microsporogenesis occurs in the microsporangium of anther.

Fourth statement is also not true because megasporogenesis and microsporogenesis give rise to megaspore and microspores respectively. Formation of mature embryo sac and pollen grains then occurs by the process megagametogenesis and microgametogenesis respectively.