Unit 2 - Cancer

Question 1

Explain how mitosis is a tightly controlled process

Answer 1

Mitosis is extremely tightly controlled
Genes in the nucleus tell cells when to divide and when to stop dividing

Question 2

What could happen to this tightly controlled process, mitosis

Answer 2

Sometimes, changes take place in these genes and that leads to the uncontrolled growth and mitosis. This produces a tumour

Question 3

State the different types of tumours

Answer 3

Benign tumours
Malignant tumours

Question 4

Describe and explain what is meant by a benign tumour

Answer 4

Benign tumours are growth of abnormal cells which are found in one area.
Benign tumours are usually contained within a membrane
These tumours do not invade other parts of the body. They stay in one place. However a benign tumour can grow very large, very quickly. If it causes pressure or damage to an organ it can be life threatening

Question 5

Describe and explain what is meant by malignant tumours

Answer 5

Malignant cells invade neighbouring tissues are move into the bloodstream.
Malignant tumour cells are classed as a cancer.
Once in the bloodstream, the malignant cells spread to different parts of the body and they form new tumours. These new tumours are secondary tumours

Question 6

Define the term tumour

Answer 6

A tumour is a mass of abnormally growing cells, formed when normal control of cell cycle is lost
and cells divide rapidly without growing and maturing.

Question 7

Define cancer

Answer 7

Cancer is the name for a malignant tumour, formed as a result of changes in cells that lead to uncontrolled growth and division

Question 8

State some risk factors for developing cancer

Answer 8

Cancers linked to genetics.
Certain types of breast cancer. Prostate cancer and cancer of the large intestine

Cancers linked to lifestyle
Lung cancer is linked to smoking. Chemicals such as asbestos and the tar found in tobacco smoke can cause mutations that trigger the formation of tumours. These chemicals are called carcinogens

Skin cancer is linked to exposure to ultraviolet light (such as: sunbathing)

Mouth and throat cancer are linked to drinking alcohol

Cancers are caused by substances in our environment. For example, radon. Radon is a radioactive gas which increases the risk of developing lung cancer. This is because radon releases ionising radiation which damages the DNA in our cells. This can cause our cells to undergo uncontrolled cell division, leading to cancer

Question 9

Describe the human cost of these non-communicable
diseases to an individual, a local community, a nation or globally

Answer 9

The human cost of non-communicable diseases is that tens of millions of people around the world die from non-communicable diseases per year

People with these diseases may have a lower quality of life or a shorter lifespan. This not only affects the sufferers themselves, but their loved ones too

Question 10

Describe the financial cost of these non-communicable
diseases to an individual, a local community, a nation or globally

Answer 10

The cost to the scientists and doctors researching and treating these diseases is huge.

Families may have to move or adapt their home to help a family member with a disease, which can be costly

Also if the family member with the disease has to give up work or dies, the family’s income would be reduce
A reduction in the people able to work can also affect a county’s economy