B3 KO Page 3

Question 1

Monoclonal antibody

Answer 1

antibodies that all stick to the exact same antigen

Question 2

Hybridoma cell

Answer 2

When white blood cells are combined with a special kind of tumour cell

Question 3

Aphids

Answer 3

Aphids are small insects that carry pathogens. They can puncture the phloem of a plant and extract the sugars.

Question 4

Nitrate deficiency

Answer 4

Lack of nitrate ions which causes stunted growth as protein synthesis is reduced

Question 5

Magnesium deficiency

Answer 5

Lack of magnesium ions which causes chlorosis as magnesium is needed to make chlorophyll

Question 6

Chlorosis

Answer 6

Leaves are yellow or white due to reduced chlorophyll thereby reducing photosynthesis

Question 7

Physical plant defence response

Answer 7

Physical barriers against pathogens such as bark, cell wall and waxy cuticle

Question 8

Chemical plant defence response

Answer 8

Chemicals produced by plants that help to prevent damage. Some plants produce antibacterial chemicals and others produce poisons so herbivores will not eat them

Question 9

Mechanical adaptations

Answer 9

Other methods plants may use to stop them being eaten such as mimicry.

Question 10

How are monoclonal antibodies produced?

Answer 10

They are produced by stimulating mouse white blood cells to make a specific antibody. The white blood cells are combined with a special kind of tumour cell to make a cell called a hybridoma cell. The hybridoma cell can both divide and make the antibody. Single hybridoma cells are cloned to produce many identical cells that all produce the same antibody. A large amount of the antibody can be collected and purified.

Question 11

How can monoclonal antibodies be used?

Answer 11

• for diagnosis such as in pregnancy tests
• in laboratories to measure the levels of hormones and other chemicals in blood, or to detect pathogens
• in research to locate or identify specific molecules in a cell or tissue by binding to them with a fluorescent dye
• to treat some diseases: for cancer the monoclonal antibody can be bound to a radioactive substance, a toxic drug or a chemical which stops cells growing and dividing. It delivers the substance to the cancer cells without harming other cells in the body