Regulating mitosis
Cell division does not normally continue without regulation. Mitosis is controlled so that cells progress through division appropriately rather than repeatedly dividing without restraint.
Genes associated with this control include oncogenes and tumour suppressor genes. Mutations involving genes that regulate the cell cycle can interfere with the mechanisms that normally restrict division.
- Normal cell-cycle control regulates how readily cells proceed through mitosis.
- Disruption of that control can permit repeated cell divisions.
- Mutations that alter this regulation can therefore contribute to the development of tumours and cancer.
Exam Tip: Build the explanation as a causal chain: mutation in a cell-cycle control gene → control of mitosis is disrupted → division can continue when it should not.