Question

Endosperm/endosperm nucleus of angiosperms is generally

• A. Haploid
• B. Diploid
• C. Triploid
• D. Tetraploid

Answer 1

Answer: (C)

Triploid

Angiosperms have a unique phenomenon of "Double Fertilisation" in which, after the release of two male gametes inside the embryo sac by the pollen tube, one male gamete i.e. the first male gamete which is too near to egg fuses with egg nucleus and this phenomenon is known as fertilisation or syngamy. During syngamy, a zygote is formed.The other male gamete i.e. the second male gamete migrates towards the secondary nucleus (formed from the fusion of two polar nuclei) and fuses with it. This phenomenon is known as triple fusion and results in the formation of a triploid primary endosperm mother cell. Primary endosperm mother cell then undergoes further divisions to form endosperm. Hence, Endosperm of angiosperms is triploid structure because it contains three sets of chromosomes, two sets from a diploid secondary nucleus and one from a male gamete.

So, the correct answer is C.