what happens during prophase

During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses. The chromatin coils and becomes increasingly compact, forming structures called chromosomes. The parent cell chromosomes, which were duplicated during the S phase of interphase, condense and become thousands of times more compact than they were during interphase. The mitotic spindle also begins to develop during prophase, as the cell's two centrosomes move toward opposite poles and microtubules gradually assemble between them, forming the network that will later pull the duplicated chromosomes apart