NEET UG 2004 — Cell Cycle and Cell Division

When a diploid female plant is crossed with a tetraploid male, the ploidy of endosperm cells in the resulting seed is:

In the somatic cell cycle:

Which one of the following precedes reformation of the nuclear envelope during $\mathrm{M}$ phase of the cell cycle?

If you are provided with root-tips of onion in your class and are asked to count the chromosomes. Which of the following stages can you most conveniently took into?