Three cells grouped together at the micropylar end and constitute _____________ in the embryo sac.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Egg apparatus
Option (1) Central cell — Incorrect. The central cell is the large cell in the middle of the embryo sac, with the two polar nuclei. It is one cell, not three.
Option (2) Polar cells — Incorrect. There are no polar cells. The book speaks of two polar nuclei, which lie in the central cell.
Option (3) Egg apparatus — Correct. At the micropylar end, two synergids and one egg cell form the egg apparatus. The egg cell is the female gamete.
Option (4) Antipodals — Incorrect. The antipodals are also three cells, but they lie at the chalazal end, opposite the micropyle.
NCERT Extract:
The Pistil, Megasporangium (ovule) and Embryo Sac – “… There is a characteristic distribution of the cells within the embryo sac. Three cells are grouped together at the micropylar end and constitute the egg apparatus. The egg apparatus, in turn, consists of two synergids and one egg cell. The synergids have special cellular thickenings at the micropylar tip called filiform apparatus, which play an important role in guiding the pollen tubes into the synergid.”