In eukaryotic cells, or cells with a nucleus, the stages of the cell cycle are divided into two major phases: interphase and the mitotic (M) phase.During interphase, the cell grows and makes a copy of its DNA.During the mitotic (M) phase, the cell separates its DNA into two sets and divides its cytoplasm, forming two new cells.Let's enter the cell cycle just as a cell forms, by division of its mother cell. What must this newborn cell do next if it wants to go on and divide itself? Preparation for division happens in three steps for interphase:G phase. During G phase, also called the first gap phase, the cell grows physically larger, copies organelles, and makes the molecular building blocks it will need in later steps.S phase. In S phase, the cell synthesizes a complete copy of the DNA in its nucleus. It also duplicates a microtubule-organizing structure called the centrosome. The centrosomes help separate DNA during M phase.During the second gap phase, or G2phase, the cell grows more, makes proteins and organelles, and begins to reorganize its contents in preparation for mitosis.During the mitotic (M) phase, the cell divides its copied DNA and cytoplasm to make two new cells. M phase involves two distinct division-related processes: mitosis and cytokinesis.In mitosis, the nuclear DNA of the cell condenses into visible chromosomes and is pulled apart by the mitotic spindle, a specialized structure made out of microtubules. Mitosis takes place in four stages: prophase (sometimes divided into early prophase and prometaphase), metaphase, anaphase, and telophase.Other types of cells divide slowly or not at all. These cells may exit the Gphase and enter a resting state called G zerophase. In G 0 phase, a cell is not actively preparing to divide, its just doing its job. For instance, it might conduct signals as a neuron or store carbohydrates as a liver cell. G 0 is a permanent state for some cells, while others may re-start division if they get the right signals.Cells take different lengths of time to complete the cell cycle. A human cell takes about 24 hours to divide,.