All living things are made up of cells. They are the smallest things that are capable of basic life-they take in nutrients when needed, they put out waste and they reproduce. Cells divide (reproduce) at least once during their life, sometimes dozens of times. Organisms rely on this, this is how they grow or repair themselves when they are damaged. A normal body has around 30 trillion cells.
Permanent gene mutations are what cause cells to malfunction. When this happens several times to the same cell it can become cancerous. This can take many years in some cases. …