When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is
- tetraploidy
- pentaploidy
- diploidy
- triploidy
Answer
(1) tetraploidy
Solution
As per NCERT, the primary endosperm nucleus is formed by the fusion of one male gamete with the two polar nuclei (triple fusion).
The female plant is diploid (2n), so its embryo sac nuclei (polar nuclei) are haploid, n each, while the male plant is tetraploid (4n), so its male gametes are 2n.
Hence the ploidy of the endosperm is n + n + 2n = 4n.
∴ The endosperm cells are tetraploid.
Answer: (1)