When a cell divides to produce two identical daughters, it uses mitosis. The process distributes replicated chromosomes equally so that each new cell receives a complete diploid set. Mitosis is essential for growth, tissue repair, and asexual reproduction.

After DNA replication, chromosomes condense, the nuclear envelope breaks down, and spindle fibers attach to centromeres. Sister chromatids separate and move to opposite poles. New nuclear membranes form and the cytoplasm divides. The result is two genetically identical cells.

Checkpoints monitor the process and can halt division if errors are detected. Uncontrolled mitosis is a hallmark of cancer. Studying mitotic mechanisms has yielded drugs that target the spindle and are used in chemotherapy. The stages—prophase, metaphase, anaphase, telophase—are readily observed under the microscope.

• Cell division producing two identical daughters
• Maintains chromosome number
• Essential for growth and repair
• Regulated by checkpoints