Describe the stages of the mitotic cell cycle, explaining the appearance of cells at each stage.

The cell cycle can be broken into two. When the cell is replicating its DNA and preparing for division, it is in interphase. Interphase cells have a nucleus with chromosomes arranged as chromatin. When the cell divides, producing two daughter cells identical to the parent cell, it is undergoing mitosis. Mitosis has four phases. Prophase: The chromosomes pair up and condense, the nuclear membrane breaks down and the spindle forms from microtubules inside the cell. Prophase cells have visible chromosomes, appearing as dark threads that shorten as they undergo coiling. Metaphase: Chromosomes are attached by the centromere to the spindle at the cell’s equator. Metaphase cells have pairs of chromatids lined up along the equator of the cell, with individual chromatids and centromeres clearly visible. Anaphase: Centromeres divide, separating the chromatids. Spindle fibres pull the sister chromatids to opposite poles of the cell – this can be seen in anaphase cells. Telophase: Spindle breaks down, chromatids are rearranged into daughter nuclei and the nuclear membrane reappears. Cytokinesis (cytoplasm division) also occurs in telophase.