Immune systems and defences

Question 1

Skin defense system

Answer 1

• physical barrier to pathogens
• secretes antimicrobial substances -
  kills pathogens

Question 2

respiration defense system

Answer 2

• hairs and mucus in nose
• mucus in trachea and bronchi
• lined with cilia

Question 3

Cilia

Answer 3

Hair-like structures that waft the mucus up to the throat where it can be swallowed to the stomach
- the stomach releases hydrochloric
acid which kills pathogens

Question 4

Phagocytosis

Answer 4

enlgufs foreign cells and digest them

Question 5

Antibodies

Answer 5

produce by white blood cell so it can bind to it and destroy

Question 6

antitoxins

Answer 6

Bind and neutralise the toxins produced by bacteria

Question 7

Pros of vaccines

Answer 7

• Protection from diseases
• control of common diseases
• prevent outbreaks (epidemic)

Question 8

Cons of vaccines

Answer 8

• dont always work (no full immunity)
• bad reactions

Question 9

How do vaccines work?

Answer 9

injecting inactive pathogens carrying the antigens so the body can produce antibodies that attack them so if the live pathogen appear the white blood cells can rapidly produce those antibodiees

Question 10

What are examples of drugs that relieve the symptoms

Answer 10

• aspirin
• paracetamol
• cough medicine

Question 11

Antibiotics

Answer 11

• kill pathogens
  -stops them from growing
• only if bacteria is the cause

Question 12

Why can you use antibiotics on viruses?

Answer 12

• made specifically to interfere with bacteria and viruses are so different
• wouldn’t be able to find them as they hide within our body cells which makes it hard to develop a drug without killing the body’s cell

Question 13

What is aspirin?

Answer 13

• painkiller
• lower fever

Question 14

Where is aspirin originally from?

Answer 14

willow trees

Question 15

What does digitalis treat?

Answer 15

• heart problems

Question 16

Where are digitalis originally from?

Answer 16

foxgloves

Question 17

What are the 3 things when testing drugs

Answer 17

• efficacy
• toxicity
• dosage

Question 18

efficacy (drug testing)

Answer 18

How well the drug works

Question 19

toxicity (drug testing)

Answer 19

how harmful the drug is
- side effects?

Question 20

dosage (drug testing)

Answer 20

how much of the drug ( concentration)
- more drug = more effect = more side
effects

Question 21

Stage 1 (drug testing)

Answer 21

• drug tested on human cells and tissues
• benefit = easily and cheaply test lots of substances
• con= doesn’t tell us how if effects an entire organism

Question 22

stage 2 (drug testing)

Answer 22

• testing on live animals (mice and mammals)
• we are mammals too so it gives us a good idea of the efficacy and toxicity of drug

Question 23

preclinical

Answer 23

Do not involve humans

Question 24

stage 3 (clinical testing)

Answer 24

• give drugs to healthy humans starting
  off with a low dose
• slowly increase dose while doctor
  keeps an eye of the patients health
  
  • checking for side effects
• aim is to find max dosage before side
  effects

Question 25

part 2 (clinical testing)

Answer 25

• give drug to a person with the
  particular illness the drug is trying to
  target
• slowly increase dose
• aim for the optimum dosage

Question 26

Optimum dosage

Answer 26

efficacy = maximized
toxicity = minimized

Question 27

How do we make sure that the results are fair and valid?

Answer 27

• clinical trails should be blind and use of placebo
• double - blind
• one half of volunteer with placebo and
  others with the real drugs
• purpose = avoid bias

Question 28

placebo

Answer 28

like the real drug but doesn’t do anything

Question 29

What happens after the completion of the drug testing?

Answer 29

results written up and peer- reviewed
- analysed by other scientists to check is
the tests were fair

Question 30

Why is it important for drugs to undergo testing?

Answer 30

• make sure its effective
• safe to use
• determine optimum dose

Question 31

Why is double-blind trails important?

Answer 31

• to avoid unconscious bias
• patients may report side effects
• researchers may pay closer attention
  to those patients