Biology
Assertion (A): One polar nucleus fuses with two sperm nuclei of a flower and develop into an endosperm during the process of fertilization.
Reason (R): The large central cell of the embryo sac contains two polar nuclei, which fuse with one male nucleus. This process is termed as 'triple fusion'.
- A is True and R is False.
- A is False and R is True.
- Both A and R are True.
- Both A and R are False.
Pollination
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Answer
A is False and R is True.
Reason — One of the two male gametes fuses with the two polar nuclei, this fusion forms the triploid endosperm nucleus. The other male gamete fuses with the egg cell to form the zygote.
The large central cell in the embryo sac contains two polar nuclei. One male gamete fuses with these two to form the endosperm, a process called triple fusion (2 polar nuclei + 1 male gamete).
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Given below is the internal structure of an ovule. Read the information below the diagram and fill in the blanks:
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