What is Cancer?
Cancer may develop when the cell cycle is not controlled. A tumour is a mass of abonormal cells that have grown when there is no need for growth and repair. Some tumours are benign, which means they tend to grow in one place and dont spread to other parts of the body. If a benign tumour is removed it is most unlikely to grow back, this doesnt mean they are harmless, it is possible for them to press on nerves or blood vessels and cause harm. Like a benign tumour on the brain is harmful.
Cancer is when malignant tumours form, these normally spread into neighbouring tissues. Cells from the tumour may break off and spread to other parts of the body, from the blood or lymph systems. This is called metastasis, here secondary tumours or metastases can start.
How is normal cell division controlled?
Genes called proto-oncogenes stop cell division. they work 2 different ways:
- May carry out genetic code for a receptor protein in the membrane. This receptor protein is the right shape for a specific growth factor…