B6 Preventing And Treating Diseases

Question 1

how does your immune system work?

Answer 1

• Your WBC detects antigens on pathogens.
• WBC makes specific antibodies to destroy the pathogen
• WBC (memory cells) remember the right antibody needed to destroy the particular pathogen .
  -If you get sick again, the antibody can be easily replicated, also the antibody stays in your blood for a long time

Question 2

how does vaccination protect you against disease?

Answer 2

• dead / inactive pathogens are injected into your body but they’re not strong enough to hurt you.
• this stimulates your WBC to make antibodies against that pathogen to prevent you from getting ill
• if you encounter the same , live pathogen again , your WBC can easily replicate the antibodies and the antibodies previously made stay in the blood for a long time, this prevents your from getting sick

Question 3

what kind of medicines heal symptoms but don’t cure disease?

Answer 3

paracetamol, aspirin, ibuprofen

Question 4

how do antibiotics work?

Answer 4

they work by killing bacterial pathogens in the body.

Question 5

why don’t antibiotics work for viruses?

Answer 5

Because viruses live and reproduce inside the cell so the antibiotic doesn’t detect anything because it only can detect pathogens outside of the cell.

Question 6

How was penicillin discovered?

Answer 6

• Alexander Fleming left a Petri dish open and it moulded.
• He discovered that the mould killed bacteria in the dish.
• He discovered that penicillium mould has penicillin in it which destroys bacteria .

Question 7

What is digitalis extracted from and what does it do?

Answer 7

-extracted from foxglove
-strengthens heartbeat.

Question 8

what is aspirin extracted from and what does it do?

Answer 8

-extracted from willow bark
-a painkiller

Question 9

how do scientists look for new drugs?

Answer 9

most new drugs are synthesised by chemists in the pharmaceutical industry. However, the starting point may still be a chemical extracted from a plant.

Question 10

Describe the 1st stage of developing drugs

Answer 10

During pre-clinical testing,
-test drugs in lab on cells, tissues and organs to see if they’re toxic and efficient.
- then, they test on animals to predict how the drug may behave in a human

Question 11

What happens during the 2nd stage of testing?

Answer 11

During clinical testing:
-low dosage given to healthy people to check for side effects
-drug tried on small number of patients to see if it cures the disease
-patient size increases to find optimal dose

Question 12

Why is testing drugs important?

Answer 12

-untested drugs may have severe side effects
-may not work
-may not be stable