B6 - Preventing and Treating Disease

Question 1

What is an antigen?

Answer 1

A unique protein on the surface of a cell

Question 2

What type of cell produces antibodies?

Answer 2

White blood cells - Lymphocytes

Question 3

What does an antibody do?

Answer 3

They join to antigens and destroy the pathogen

Question 4

How does immunity occur (naturally)?

Answer 4

Upon first encountering a new pathogen, white blood cells need to create new antibodies to destroy them.
Some white blood cells will “remember” how to make these specific antibodies if the same pathogen enters the body.
This allows the WBCs to kill the pathogens quickly, before they can have any effect upon the body, making you immune

Question 5

What does a vaccine contain?

Answer 5

A dead or inactivated form of a disease-causing microorganism

Question 6

What does a vaccine do?

Answer 6

It causes immunity through stimulating the WBCs to create antibodies to kill the inactivated pathogen
Now that the WBCs know how to make these antibodies, they can defend against the living version of the pathogen

Question 7

What types of disease can vaccines protect you against?

Answer 7

Bacterial such as Tetanus and Diphtheria

Viral such as Polio, Measles, and Mumps

Question 8

Give an example of a disease that has been eradicated through vaccines

Answer 8

Smallpox

Question 9

What disease do doctors think vaccines can soon eradicate?

Answer 9

Polio

Question 10

What is herd immunity?

Answer 10

Immunising a large proportion of the population to reduce the spread of a pathogen and so a disease

Question 11

What would happen if the herd immunity is lost?

Answer 11

The disease would reappear

Question 12

Give an example of when herd immunity was lost.

Answer 12

1970s UK
There was a scare about the safety of the whooping cough vaccine
Vaccination rates fell from 80% to 30%
In the following years, thousands of children got whooping cough again and many died
People began to use vaccines again so the herd immunity was regained

Question 13

How does the World Health Organisation want to achieve global herd immunity for measles?

Answer 13

WHO wants 95% of children to have two doses of measles vaccine to give global herd immunity

Question 14

What are the current statistics of achieving global herd immunity for measles?

Answer 14

85% of children receive the first dose

56% of children receive the second dose

Question 15

Name two common painkillers

Answer 15

Paracetamol

Aspirin

Question 16

What can painkillers do?

Answer 16

Relieve headaches and sore throats

Reduce pain

Question 17

What do painkillers NOT do?

Answer 17

Kill viruses, bacteria or cure the disease

Question 18

What type of drugs are used to cure bacterial diseases?

Answer 18

Antibiotics

Question 19

What are antiseptics used for?

Answer 19

Killing bacteria outside the body

Question 20

Why are antiseptics and disinfectants not used inside the body?

Answer 20

They are very poisonous and they would kill you

Question 21

When did antibiotics first become widely available?

Answer 21

The 1940s

Question 22

Who discovered Penicillin and what is Penicillin an example of?

Answer 22

Alexander Fleming

Antibiotics

Question 23

How do antibiotics work?

Answer 23

They kill the bacterial cells inside your body, without damaging your own cells

Question 24

Why can antibiotics not be used on viruses?

Answer 24

Viruses invade the human’s cells and reproduce inside them
Antibiotics do not effect a human’s cells and so the viruses are not killed
It is extremely difficult to develop drugs that will kill viruses without damaging the body’s cells at the same time

Question 25

How do antibiotics enter the body?

Answer 25

Usually through a syrup or a pill

If very ill, they could be put straight into the bloodstream

Question 26

How do bacteria become resistant to antibiotics?

Answer 26

Evolving / mutating

Question 27

Where can drugs be extract from?

Answer 27

Plants or microorganisms such as moulds

Question 28

What two drugs are extracted from foxgloves and what is their purpose?

Answer 28

Digitalis and Digoxin

They have been used since the 18th century to help strengthen the heartbeat

Question 29

What drug originates from the bark of willow trees?

Answer 29

Aspirin

Question 30

How was penicillin discovered?

Answer 30

Alexander Fleming was careless and often left the lids off of his culture plates
After one holiday, he noticed mould growing on lots of the plates
He also noticed a clear ring in the jelly around some of the mould.
He realised that something had killed the bacteria
“Penicillin” was named after “Penicillium” (the mould that produced it