Monoclonal antibodies - Biology Paper 1

Question 1

What are monoclonal antibodies?

Answer 1

Identical copies of one type of antibody

Question 2

What are antibodies produced by?

Answer 2

Lymphocytes (white blood cells)

Question 3

How are monoclonal antibodies made?

Answer 3

An antigen is injected into a mouse

The mouse naturally produces lymphocytes, which produce antibodies specific to the antigen

Spleen cells which produce the lymphocytes are removed

The b-lymphocytes are fused with tumour cells to make a hybridoma

The hybridoma cells can be cloned to produce many monoclonal antibodies specific to the antigen

Question 4

What are monoclonal antibodies used for?

Answer 4

Pregnancy tests, diagnosis, treating disease

Question 5

How are monoclonal antibodies used in pregnancy tests?

Answer 5

Pregnancy test kits use monoclonal antibodies. These have been designed to bind with a hormone called HCG which is found only in the urine of pregnant women. Monoclonal antibodies are attached to the end of a pregnancy test stick onto which a woman urinates. If she is pregnant, HCG will be present in her urine and will bind to the monoclonal antibodies on the test stick. This will cause a change in colour or pattern which will indicate pregnancy. These specific monoclonal antibodies in the pregnancy test will only bind with HCG.

Question 6

What does the control window on a pregnancy test do?

Answer 6

It makes sure the tests has worked properly - the control window should go blue even when a person is not pregnant

Question 7

How can monoclonal antibodies identify a cancerous tumour?

Answer 7

Cancerous cells have antigens. Monoclonal antibodies can be designed to bind specifically with these antigens. When injected into a person’s body, the monoclonal antibodies will bind with these cancer cells and clump them together. This makes it easier to identify a cancerous tumour, which can then be treated or removed.

Question 8

How can monoclonal antibodies be used to treat cancer?

Answer 8

• anti cancer drugs can be attached to the monoclonal antibodies. This drug can stop the cancer cells from growing and dividing, or kill them.
• monoclonal antibodies can also encourage your immune system to attack the cancer cells directly

Question 9

How can monoclonal antibodies be used to identify disease?

Answer 9

monoclonal antibodies have been attached to dyes that will glow fluorescent under UV light. This can make disease identification much easier.

Question 10

What is the problem with monoclonal antibodies?

Answer 10

There’s many unwanted side effects