Question

Assertion (A) : In angiosperms, each cell in the embryo sac is haploid.
Reason (R) : Embryo sac formation is preceded by meiosis.

• A. Both A and R are correct and R is the correct explanation of A.
• B. A is correct but R is incorrect.
• C. Both A and R are incorrect
• D. Both A and R are correct and R is not the correct explanation of A.

Answer 1

The correct option is A Both A and R are correct and R is the correct explanation of A.

In angiosperms, the female gametophyte is referred to as the embryo sac.
Each ovule generally consists of a diploid megaspore mother cell which undergoes meiotic division giving rise to four haploid megaspores. Out of these, three normally degenerate and only one megaspore remains functional.
The functional megaspore undergoes repeated mitosis to give rise to a 7-celled 8-nucleated embryo sac.
Each embryo sac has-

• a three-celled egg apparatus which is composed of one egg cell and two synergids
• three antipodal cells
• two polar nuclei within a large central cell.