human defense system

Question 1

skin

Answer 1

acts as a physical barrier

3 layers

outer layer is dead cells

when there is a cut or braze it heals itself

Question 2

nose

Answer 2

physical barrier

contains hairs

traps pathogens before the enter lungs

mucus is removed when nose is blown

Question 3

tears

Answer 3

antiseptic

contains enzymes

chemical barrier

Question 4

earwax

Answer 4

carries pathogens

Question 5

trachea and bronchi

Answer 5

trachea lined with ciliated cells

hairs on ciliated cells waft mucus and pathogens

Question 6

stomach

Answer 6

chemical barrier

contains acid

hydrochloric acid kills pathogens

Question 7

Immune system

Answer 7

once pathogens are inside body

White blood cells engulfs and breaks it down

Question 8

Antigen

Answer 8

Proteins on pathogens surface

They body uses these to recognise as foreign and attacks them

Question 9

Phagocyte

Answer 9

Engulfs pathogen

Digests using enzymes

Question 10

B-cells

Answer 10

Produce “y” shaped antibodies

attaches onto specific antigen

The bacteria is clumped together- then engulfed by phagocytes

Question 11

Antibody

Answer 11

Takes 3-4 days to find correct antibody to fit antigen

Only lasts for a few days

Memory cells are produced

Question 12

Memory cells

Answer 12

made when antibodies die out

When the same pathogen tries to cause harm

Memory cells mass produce

Question 13

Antitoxins

Answer 13

White blood cells produce antitoxins which attach to toxins produced by pathogens

Neutralises toxins

Antitoxin can only neutralise one specific toxin

Question 14

White blood cells…

Answer 14

Are produced in bone marrow enter bloodstream

Lymph nodes are pockets of wb cells around body

Question 15

Vaccine

Answer 15

Dead or inactive pathogen
injected into body

develops immunity to a disease

Makes memory cells

Question 16

initial exposure + primary response

Answer 16

0 antibodies

3-4 days later antibodies gradually increase

after peak it gradually decreases not to 0

memory cells stay

Question 17

Secondary infection

Answer 17

when same pathogens infect

memory cells mass produce in short time

faster and greater response

More Memory cells left in second exposure

Question 18

Herd immunity

Answer 18

majority of the population gets vaccinated against a disease

Builds herd immunity

Reduces chance of spread

Question 19

painkillers

Answer 19

chemicals that make us fell better by reliving symptoms
headaches
sore throat

Does not kill pathogens
paracetamol
ibropufen

Question 20

Drugs

Answer 20

Chemical that changes the way a part of your body works

Question 21

why do drugs need to be tested

Answer 21

safety

effectiveness

dosage

Question 22

safety

Answer 22

Some drugs are toxic and may be harmful

Question 23

effectivenesss

Answer 23

how well drug works to improve symptoms

Question 24

dosage

Answer 24

must be controlled

too much could he toxic

Question 25

anti biotics

Answer 25

kill/ slow growth of bacteria

includes penicillin and amoxicillin

only works on bacterial disease

Question 26

penicillin

Answer 26

first antibiotic

found by alexander fleming

bacteria on petri dish was killed by penicillium mold

Question 27

how anti biotics work strains

Answer 27

damages bacterial cell not host cell

some antibiotic due to overuse become less effective

due to antibiotic resistance

bacteria mutates

Question 28

viral disease

Answer 28

difficult to treat as they reproduce inside host cell

antiviral drugs slow down viral development

virus changes antigens means new drugs needed

Question 29

problems with anti biotics

Answer 29

less effectiveness happens due to

overuse
failing to complete full course
antibiotics in farming

Question 30

over use

Answer 30

unnecessary prescribed antibiotics

Question 31

course completion

Answer 31

ensures all bacteria are killed

none survive to mutate and cause new strains

causing resistance

Question 32

agriculture

Answer 32

prevent disease

keep animals well

high use of antibiotics - spread of antibiotics

cause resistance

Question 33

ways to reduce antibiotic resistance

Answer 33

only take antibiotic when needed

treat specific bacteria with specific antibiotics

high hygiene levels

isolate patient

Question 34

plant extracts

Answer 34

drug sources

willow bark = salicylic acid

digitalis = from foxgloves= heart drug

Question 35

thalidomide

Answer 35

medical drug causing serious damage to unborn babies

sleeping pill morning sickness in preg

damage in development

legs / arm short undeveloped

now used for leprosy / bone cancer