B6: Preventing and Treating Disease

Question 1

What is vaccination?

Answer 1

Introducing small quantities of dead or inactive forms of pathogen into the body. Because it is dead or inactive, it cannot lead to the disease in the patient. This stimulates the white blood cells to produce antibodies against the dead or inactive pathogen. At the same time, the wbcs divide by mitosis, which can stay for a while. Thus, if the same pathogen is encountered again, wbcs can now combat it faster

Question 2

What is herd immunity?

Answer 2

A large number of people who are vaccinated

Question 3

What is the purpose of herd immunity?

Answer 3

If many people are vaccinated, then they do not develop a disease, thus they cannot pass it onto those who aren’t

Question 4

What was the first antibiotic discovered?

Answer 4

Penicillin

Question 5

What are antibiotics?

Answer 5

Substances which kill infective bacteria inside the human body without harming the body cells

Question 6

What is antibiotic resistance?

Answer 6

If antibiotics are overused, they can cause the bacteria to evolve, thus they are no longer affected by the antibiotic

Question 7

What are some rules of using antibiotics?

Answer 7

Specific antibiotics are used for specific bacteria
Cannot kill viruses

Question 8

What are painkillers?

Answer 8

Used to relieve symptoms of pain, but do not kill pathogens

Question 9

Why are viral diseases harder to treat than bacterial diseases?

Answer 9

Viruses live and reproduce inside cells, therefore it’s hard to develop drugs to kill them without damaging healthy tissue

Question 10

Name 3 medicines, their function and where they’re found

Answer 10

Digitalis - heart drug - foxglove
Aspirin - painkiller - willow
Penicillin - antibiotic - penicillium mould

Question 11

How are drugs made nowadays?

Answer 11

Synthesised in labs, but the starting point is still often extracted from a plant

Question 12

What are the 3 necessary drug trials?

Answer 12

Toxicity - is it poisonous to humans
Efficacy - is it effective
Dosage - how much is needed for it to work

Question 13

Describe the first and second stage of drug testing

Answer 13

Preclinical test - drug is tested on cells, tissues or live animals
Clinical test - drug is tested on healthy volunteers who are given a small dosage. If the drug is deemed safe, then the testing continues to find the optimal dosage

Question 14

What is a placebo?

Answer 14

A tablet or injection with no active drug

Question 15

What is a blind test?

Answer 15

Giving the patient a placebo/ not telling them the supposed effects of a drug to test the psychological effects

Question 16

What is a double blind test?

Answer 16

Neither the patient nor the doctor know whether the patient is getting an actual drug or a placebo,
to stop bias

Question 17

What is a monoclonal antibody?

Answer 17

A colony of antibodies of the same type

Question 18

What produces antibodies?

Answer 18

White blood cells called lymphocytes produce antibodies against anything foreign, called antigens

Question 19

What are some uses of monoclonal antibodies?

Answer 19

Pregnancy tests
Certain cancer treatments

Question 20

How are monoclonal antibodies produced?

Answer 20

A mouse is injected with an antigen which will stimulate the lymphocytes to produce specific antibodies against the antigen. These can then be collected (these cannot divide by mitosis).

Question 21

How can monoclonal antibodies be reproduced?

Answer 21

They are fused with a tumour cell (myeloma cell), which divide quickly by mitosis, producing a hybridoma cell, which can produce antibodies and divide by mitosis. We now allow the hybridoma cell to divide by mitosis to form a clone, and the antibodies produced are all identical