Question

Perisperm is:

• A. degenerate part of synergids
• B. peripheral part of endosperm
• C. degenerate part of secondary nucleus
• D. remnant of nucellus

Hint:

Perisperm is the nutritive tissue surrounding the embryo in certain seeds and developing from the nucellus of the ovule. 

Answer 1

The Correct Option is D

The given question asks about the definition of "Perisperm" in a biological context. Let us examine each option and determine which best describes perisperm.

1. Option 1: Degenerate part of synergids
   • Synergids are cells in the embryo sac of flowering plants that help guide the pollen tube to the ovule. Degeneration of synergids occurs once the pollen tube reaches them. However, this degeneration does not form perisperm.
2. Option 2: Peripheral part of endosperm
   • The endosperm is a tissue produced inside the seeds of most flowering plants following fertilization. It surrounds the embryo and provides nutrition. "Perisperm" is not a part of the endosperm.
3. Option 3: Degenerate part of secondary nucleus
   • The secondary nucleus is involved in the formation of the endosperm. Degeneration of a secondary nucleus as a process does not result in perisperm.
4. Option 4: Remnant of nucellus
   • The nucellus is part of the ovule and provides nutrition to the developing embryo and endosperm. Sometimes, after fertilization, remnants of the nucellus persist in the seed, and these remnants are referred to as the "perisperm". Thus, this option correctly describes the perisperm.

Based on the explanations above, the correct answer is the remnant of nucellus, as perisperm is indeed the residual tissue from the nucellus present in certain seeds.