There are then two complete sets of chromosomes in the nucleus. The chromosomes are now coiled tightly. The coiled chromosomes can be seen through a microscope. The nuclear membrane begins to disappear at this time. There is no longer a division between the nucleus and the cytoplasm.
Chromosomes become thicker and shorter, and are now easier to see.
The nuclear membrane has faded away. The pairs of identical chromosomes line up in the center of the cell. Thin fibers called spindle fibers are attached to the chromosomes. The pairs of identical chromosomes separate from one another. The chromosomes move toward the center of each new cell.