Question: 92. A typical angiosperm embryo sac at maturity is:
(1) 8-nucleate and 7-celled
(2) 7-nucleate and 8-celled
(3) 7-nucleate and 7-celled
(4) 8-nucleate and 8-celled
Answer: Option (1)
Explanation:
In angiosperms, the typical embryo sac develops by the monosporic (Polygonum) type of development.
The mature embryo sac contains one egg cell, two synergids, three antipodal cells, and one central cell.
The central cell contains two polar nuclei, so the total number of nuclei becomes eight.
The number of cells is seven because the two polar nuclei are present within a single central cell.
Therefore, a typical mature angiosperm embryo sac is 8-nucleate and 7-celled.