Eukaryotic cells contain a nucleus and organelles. During the cell cycle, the cell goes through a period called interphase. During this phase, the cell grows and synthesizes everything it will need to function. It will also replicate the chromosomes that are present in the nucleus so that when it undergoes mitotic cell division, it will have two complete sets of chromosomes, one set for each daughter cell. During mitosis, the doubled chromosomes or chromatids which are attached by centromeres, will attach to the spindle fibers. The nuclear membrane will disappear and the chromatids will line up in the equator of the cell. Later on, the chromatids separate and migrate to opposite poles. Eventually, a nucleus will re-form around each set of chromosomes, cytoplasmic division or cytokinesis will occur, and the end result is two smaller, but identical daughter cells.