Question

In a typical Polygonum type of embryo sac

• A. The largest cell becomes diploid just prior to triple fusion.
• B. The egg apparatus lies at chalazal end
• C. Wall formation occurs around seven nuclei so that it becomes seven celled
• D. Egg has chalazal vacuole

Answer 1

Answer: (A)

The largest cell becomes diploid just prior to triple fusion.

A fully organised Polygonum type of embryo sac is a 7-celled 8-nucleate structure. The cells of egg apparatus present at micropylar end and antipodal cells at the chalazal end are haploid whereas the central large cell is diploid, ie, contains two polar nuclei. Triploid endosperm is formed after triple fusion, ie, the fusion of second male gamete with polar nuclei.

So, the correct option is 'The largest cell becomes diploid just prior to triple fusion'.