Question

The ploidy level of primary endosperm nucleus in Oenothera before

fertilization is ................

• A. $n$
• B. $3n$
• C. $2n$
• D. $5n$

Answer 1

The correct option is C $2n$

Primary endosperm nucleus - the nucleus formed by the fusion of two polar nuclei in the embryo sac of a seed plant prior to fertilization - called also secondary nucleus. Haploid parthenogenesis occurs in plants like Oenothera. The ploidy level of primary endosperm nucleus in Oenothera before fertilization is diploid (2n).