Question

Primary endosperm nucleus (PEN) is formed by the fusion of

• A. 2 antipodal cell nuclei + 1 male gamete nucleus
• B. 2 polar nuclei + 1 synergid cell nucleus
• C. 2 polar nuclei + 1 male gamete nucleus
• D. 1 polar nucleus + 1 antipodal cell nucleus + 1 synergid cell nucleus

Answer 1

The correct option is C 2 polar nuclei + 1 male gamete nucleus

Primary endosperm nucleus

Fusion of the haploid nucleus of one of the male gametes with the two haploid polar nuclei of the central cell, which remain fused as a diploid secondary nucleus, results in the formation of a triploid primary endosperm nucleus or PEN. This process is called triple fusion.

The other male gamete fuses with the haploid egg cell to form the diploid zygote. The synergids and antipodal cells degenerate after fertilisation.


Final answer
c. 2 polar nuclei + 1 male gamete nucleus.