Candidates should be able to relate their understanding of the cell cycle to cancer and its treatment.

If there is a change in the DNA that controls the cell cycle, there can be an increase in the speed that cells grow at.

One cell with this mutation will rapidly divide into to, and this will continue to create a large group of cells, called a tumour.

These tumours are potentially disruptive to the functions of organs, as we know cancer takes many lives.

Chemotherapy is the use of chemicals to inhibit the cell cycle. They effect parts of the cell cycle for example: stopping spindle formation in the metaphase; stopping DNA replication during synthesis.

These chemicals effect the cycles of all cells in the body, but they will have a bigger effect the faster the cycle. This means that cancer cells are significantly slowed, but so are other quickly replicating cells are too, like hair cells.