In which phase of cell division do the nuclei formed at both polar regions appear?

At which stage of the cell cycle does colchicine arrest the spindle?

Identify the structure labeled as $A$ and state the phase shown in the image.

Why are chromosomes extended in the cytoplasm during metaphase?

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

Mitotic spindle initiates during