Question

Choose the odd one out of the following terms given and name the category to which others belong:

(i) Aster, chromosome, spindle fibres, cytokinesis, centromere

Answer 1

Karyokinesis

1. Karyokinesis is the first stage of M - phase.
2. In karyokinesis, the parent nuclei divides to form two daughter nuclei.
3. During prophase of cell division, aster is formed surrounding the centrioles. In animal cells, the cell poles are formed by the asters.
4. Similarly, chromosomes are also formed during karyokinesis and they decondense at the end of karyokinesis.
5. Spindle fibres become prominent when the cell cycle enters the metaphase and the chromosomes get aligned at the equator of the cell.
6. Centromere is seen in all animal cells during karyokinesis. It holds the two sister chromatids together.

Cytokinesis

Cytokinesis is a completely different event of M – phase which occurs after karyokinesis.

Hence, the odd one is cytokinesis. The other belongs to karyokinesis.