What happens during prophase?

During prophase, chromatin condenses into chromosomes, and the nuclear envelope, or membrane, breaks down. In animal cells, the centrioles near the nucleus begin to separate and move to opposite poles (sides) of the cell

Explanation:

BTW, CK-12 Foundation is a good place for biology help. I learned this stuff about the cell cycle and whatever at the beginning of the school year, so I know what this is.