Defence against Diseases - Vaccination + Antibiotics, Painkillers + Discovery and Development of drugs

Question 1

what does vaccination introduce

Answer 1

• dead or inactive forms of a pathogen into the body to stimulate the white blood cells to produce antibodies

Question 2

describe the process on which vaccines prevent illness

Answer 2

1. Dead / inactive pathogens are introduces into body, often by injection
2. White blood cells in body produce antibodies in response to antigens from vaccine.
3. antibodies destroy antigens with no risk of you getting the disease
4. If pathogen re-enters your system again, your immune system can produce correct antibodies quickly –> preventing infection –> now immune

Question 3

what are the pros of vaccination

Answer 3

• helped reduce number of lots of communicable diseases that were v. common
• prevent large outbreaks of certain diseases –> larger no. of population are vaccinated

Question 4

what are cons of vaccinations

Answer 4

• vaccines don’t always work –> sometimes don’t provide immunity
• some suffer side effects - rare

Question 5

name an example of antibiotics

Answer 5

penicillin

Question 6

how do antibiotics treat diseases

Answer 6

• help cure bacterial diseases by killing infective bacteria inside the body
• important that **specific bacteria ** are treated with specific antibiotics

Question 7

why do antibiotics not work against viruses and why would it be difficult?

Answer 7

viruses live inside host cells –> antibiotics can’t reach them
- difficult to develop drugs that kill viruses without also damaging body’s tissues

Question 8

how has antibiotics had a positive effect in treatment

Answer 8

greatly reduced deaths causes by communicable diseases worldwide

Question 9

what are the negative side effects of antibiotics

Answer 9

emergence of strains resistant to antibiotics have emerged

Question 10

what are painkillers used for

Answer 10

• to treat symptoms of disease, but do not kill pathogen
• only ** reliving the symptoms pain**

Question 11

how were drugs traditionally extracted and why?

Answer 11

• from plants and ** microorganisms**
• plants produce variety of chemical that they use to defence themselves against pests + pathogens

Question 12

give me 3 examples of original drugs, what they were extracted from and what they treat:

Answer 12

• Digitalis: Foxgloves, Heart conditions
• Aspirin: Willow, Painkiller + Reduces fever
• Penicillin: Penicillium mould, Kills bacteria

Question 13

currently how are drugs extracted

Answer 13

• 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 14

what are new drugs tested for:

Answer 14

• Toxicity
• Efficacy
• Dose

Question 15

what are preclinical testing done on in laboratories:

Answer 15

• cells (human)
• tissues (human)
• 2 different types of live mammals (rabbits / mice)

Question 16

who are clinical trials tested on and why

Answer 16

healthy volunteers + patients (too see if side effect occur)

Question 17

describe the first 2 stages of clinical trials:

Answer 17

1. Very low doses of drugs given to healthy volunteers
2. if drug is found to be safe–> further clinical trials care carried out on individuals with the appropriate disease / disorder to find the optimum dose –> does that has best effect with minimal side effects

Question 18

what are placeboes

Answer 18

tablet/capsules that look identical to the new drug but contain no active ingredient

Question 19

why are placebos used

Answer 19

to ensure **valid + reliable data* is collected with no bias

Question 20

what are the 3 types of blind trials

Answer 20

• single blind trial
• double blind trial
• triple blind trial

Question 21

what is a single blind trial

Answer 21

the patient doesn’t know if they are being given a drug or a placebo, but doctor knows what the patient takes

Question 22

what is a double blind trial

Answer 22

some patients are given a placebo and some get the new drug but neither patient or doctor knows if the patient is given a placebo or not until trial is complete

Question 23

what is a triple blind trial

Answer 23

some patients are given a placebo and some get the new drug but neither patient or doctor or the statisicians knows if the patient is given a placebo or not until trial and data processing is complete

Question 24

what is the purpose of these blind trials

Answer 24

• allows for the placebo effect : when patient expects to feel better as they are taking medication
• also prevents subconscious bias from doctors when reporting how effective the drug has been

Question 25

what is the last step of drug trialling

Answer 25

Peer review : results of testing and trailing are published only after scrutiny by peer review

Question 26

what is peer review

Answer 26

when other scientists check the work of the original scientists to make sure the testing has been rigorous enough

Question 27

what is the importance of a peer review

Answer 27

• ensure testing has been rigorous enough
• prevent false claims