Which of the following options accurately defines perisperm in relati…

The correct answer is Option (4) → Remnant of the nucellus

Perisperm is a part of some seeds that comes from the nucellus, the food-rich mass of cells of the ovule. In most seeds the nucellus is used up, but in a few seeds, such as black pepper and beet, remnants of the nucellus persist in the mature seed. This residual, persistent nucellus is called the perisperm.

Option (1) Degenerate part of synergids — Incorrect. The synergids are two cells of the egg apparatus at the micropylar end of the embryo sac. One of them receives the pollen tube, and they do not persist as a seed tissue.

Option (2) The peripheral part of the endosperm — Incorrect. The endosperm is the food tissue formed from the primary endosperm cell after triple fusion. Any part of it, outer or inner, is still endosperm, not perisperm.

Option (3) Degenerated part of the primary endosperm nucleus — Incorrect. The primary endosperm nucleus is triploid and divides to form the endosperm. Perisperm has nothing to do with it; it comes from the diploid nucellus.

Option (4) Remnant of the nucellus — Correct. Perisperm is the residual, persistent nucellus found in some seeds such as black pepper and beet.

NCERT Extract:
Seed – “… Mature seeds may be non-albuminous or ex-albuminous. Non-albuminous seeds have no residual endosperm as it is completely consumed during embryo development (e.g., pea, groundnut). Albuminous seeds retain a part of endosperm as it is not completely used up during embryo development (e.g., wheat, maize, barley, castor). Occasionally, in some seeds such as black pepper and beet, remnants of nucellus are also persistent. This residual, persistent nucellus is the perisperm.”