In which phase of cell division can chromosomes be counted most easily?

$A$: The complete disintegration of the nuclear envelope marks the start of metaphase.
$R$: Chromosomes are distinct with two chromatids at this stage.

In which phase of mitosis do chromatids,each possessing an independent centromere,form?

Which part of the cell disappears during mitosis?

In which phase do new nuclei come into existence?

Identify the correct sequence of stages in mitotic cell division.