Answer:
Lining up of chromosomes in the cell .
Step-by-step explanation:
Prophase begins with the Thickening of chromosome. Chromosomes are clearly visible inside the nucleus. each chromosome splits longitudinally to form two chromatids.
The centriole in the centrosome of animal cell divides into two. The centrosphere set the centrioles free. Centrioles develop very fine eye-lash like thread called aster rays. the two asters start moving towards the opposite poles. By the end of prophase they reach at the opposite poles.