Mitosis Cell Division

Why do cells undergo Cell Division? Cell size- larger cells are less efficient, cells divide to keep cells small Growth of an organism- the more cells an organism has, the larger it is. All multicelled life starts as a single cell after fertilization then grows. Reproduction- single celled organisms divide by Mitosis to reproduce.

Cell Life Cycle Interphase- the phase a cell stays in longest. Time of growth, DNA replication and preparation for division Mitosis- Actual time of cell division. Nuclear division and separation of chromosomes. Cytokinesis-final phase of division where cytoplasm is divided and cell splits in two.

Cell cycle:

Overview of Mitosis Phases Prophase- DNA has already replicated. Nuclear Membrane dissolves and Chromosomes shorten and thicken. Centrosomes separate and move to opposite ends of the cell.

Overview of Mitosis Metaphase- Chromosomes have aligned themselves along the equator of the cell. Spindle fibers are present.

Overview of Mitosis Anaphase- Phase in which the chromosomes begin to separate and move apart. Chromosomes are pulled by the spindle fibers toward the centrioles.

Overview of Mitosis Telophase- The last phase of Mitosis. Nuclear membranes re-form around the new nuclei. Chromosomes lengthen and become invisible. In animal cells cleavage furrow forms, in Plants, a Cell Plate

Cytokinesis- Final stage of the cell Life Cycle Cytoplasm and its contents are divided and the original cell pinches into two new daughter cells.