Which element is required for the formation of the bipolar spindle during cell division?

What is the number of chromosomes in human cells during the following phases: Metaphase,Metaphase-$I$,and Metaphase-$II$,respectively?

Which of the following events is inconsistent with the events occurring during interphase?

Compare the statements $A$ and $B$.
$Statement A$: Synthesis of $DNA$ takes place in the $S$-phase of interphase.
$Statement B$: Every chromosome,during metaphase,has two chromatids.
Choose the correct description.

Which of the following pairs is incorrect?

Based on the figures given below,select the option that shows the correct sequence of cell division.