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In eukaryotic organisms—plants, animals, and many protists—mitosis is the engine that drives growth, regeneration, and the continuous renewal of cells essential for survival and reproduction.

What Is Mitosis?

Mitosis is a precise, asexual division that duplicates a parent cell’s genome so that each daughter cell receives an identical set of 46 chromosomes. The process occurs in every somatic (non‑reproductive) cell, ensuring that tissues maintain their structure and function over time. Short‑lived cells such as blood, skin, hair, and gut cells must continuously renew through mitosis to keep the organism functional.

Some species, like starfish, rely on mitosis of undifferentiated stem cells to regrow missing limbs after injury.

The Stages of Mitosis

• Interphase: The nucleus copies its DNA in preparation for division.
• Prophase: Chromosomes condense, becoming visible, while the nuclear membrane dissolves.
• Metaphase: Chromosomes line up at the cell’s equator, held in place by the spindle apparatus (animals) or microtubules (plants).
• Anaphase: Sister chromatids separate and are pulled toward opposite poles.
• Telophase: Nuclear envelopes reform around the two sets of chromosomes, forming two nascent nuclei.
• Cytokinesis: The cytoplasm divides—animal cells pinch in at the middle, plant cells build a new cell wall via a cell plate—producing two genetically identical daughter cells.

Mitosis in Wound Healing

When skin is scraped or a blood vessel is damaged, adjacent cells immediately enter the cell cycle, proliferating to replace lost tissue. In children, this rapid mitotic activity results in almost scar‑free healing, illustrating mitosis’s vital role in regeneration.

Mitosis Versus Meiosis

While both processes occur in plants and animals, their purposes differ. Mitosis maintains organismal integrity; meiosis generates genetic diversity by halving chromosome numbers and shuffling alleles during the formation of gametes. This diversity is essential for a species’ resilience against disease and environmental change. When biodiversity is limited, a population may be driven to the brink of extinction by new diseases or shifting conditions.

When Mitosis Goes Wrong

Errors in chromosome segregation can activate oncogenes or inactivate tumor‑suppressor genes, leading to uncontrolled cell proliferation and cancer. Although many mitotic mistakes trigger cell death, rare alterations may provide a selective advantage, contributing to evolution. Maintaining the fidelity of mitosis is therefore critical for health and longevity.

For further reading, see the links to peer‑reviewed studies on mitotic fidelity and cancer genetics.