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Question 1

how do vaccines work?

Answer 1

inject small amount of dead or inactive pathogens which have antigens. these cause the body to produce antibodies to attach to them. (triggers an immune response)
the antibodies produced are stored as memory cells, so when infected, body can produce those antibodies much quicker

Question 2

pros of vaccines

Answer 2

• help control lots of communicable diseases that were once very common - polio, measles
• big outbreaks (epidemics) can be prevented if a large percentage of the population is vaccinated. fewer people can pass on the disease so fewer can catch it. (herd immunity)

Question 3

cons of vaccination

Answer 3

they do not always work - do not always give immunity
could sometimes have a bad reaction to the vaccine

Question 4

antibiotics

Answer 4

treat bacterial disease by stopping bacteria cellular processes so do not work against viruses as they reprodice inside cells - the cause of the disease

Question 5

painkillers

Answer 5

treat the symptoms of the disease, not the disease

Question 6

why is it difficult to treat viral diseases?

Answer 6

viruses reporduce inside cells so killing viruses would also cause harm to body cells

Question 7

ways to prevent resistant bacteria

Answer 7

• avoid overuse of antibiotics
• do not use antibiotics in non-serious infections
• do not use for viruses
• patients should finish whole course of antibiotics so that all bacteria are killed and none are left to mutate to resistant strains
• reduce agricultural use of antibiotics

Question 8

how to reduce spread of resistant strains

Answer 8

• good hygiene practices like hand washing and sanitisers
• isolation of infected patients

Question 9

where does digitalis come from

Answer 9

foxgloves - its a heart drug (strengthens heart beat)

Question 10

where does aspirin come from

Answer 10

willow bark and is a pain killer

Question 11

where does penicillin come from

Answer 11

penicillium mould, alexander flemming. is an antibiotic

Question 12

what are drugs tested for?

Answer 12

toxicity, efficacy, dosage

Question 13

preclinical testing

Answer 13

in a lab using cells, tissues, and live animals

Question 14

clinical trials

Answer 14

uses healthy volunteers, then patients
- low does of the drug are given at start of trial
- if drug is safe, further clinical trials are carried out for optimum dose of drug
- can be double blind and iven placebos

Question 15

why are placebos used

Answer 15

to remove the psychological effect of the drug. it is a medicine that does not contain the active drug being tested

Question 16

what are monoclonal antibodies

Answer 16

made by identical immune cells which are clones of the parent cell
the antibodies are specific to one binding site on one protein antigen and so are able to target a specific chemical or specific cells in the body

Question 17

how are monoclonal antibodies produced?

Answer 17

• stimulating mouse lymphocytes to make a
  particular antibody.
• the lymphocytes are combined with a particular kind of tumour cell to make a cell called a hybridoma cell.
• the hybridoma cell can both divide and make the antibody.
• single hybridoma cells are cloned to produce many identical cells that all produce the same antibody.
• a large amount of the antibody can be collected and purified.

Question 18

uses of monoclonal antibodies

Answer 18

• for diagnosis like pregnancy tests
• in labs to measure hormone levels/chemicals in blood/ pathogens
• in research to locate/identify specific molecules in cell or tissue by binding with fluorescent dye
• to treat some diseases

Question 19

how monoclonal antibodies used to treat cancer

Answer 19

monoclonal antibody is bound to radioactive substance/toxic drug/chemical which stops cells growing and dividing.
it delivers the substance to the cancer cells without harming other cells in the body.

Question 20

disadvantages of monoclonal antibodies

Answer 20

• cause more side effects than first expected
• expensive
• more difficult than expected

Question 21

symptoms of plant disease

Answer 21

• stunted growth
• spots on leaves
• areas of decay
• growths
• malformed stems or leaves
• discolouration
• presence of pests

Question 22

how are plant diseases identified?

Answer 22

• reference to gardening manual or website
• taking infected plants to lab to identify pathogen
• using testing kits that contain monoclonal antibodies

Question 23

nitrate deficiency in plants

Answer 23

stunted growth as nitrate ions are needed for protein synthesis

Question 24

magnesium deficiency in plants

Answer 24

chlorosis as magnesium ions are needed to make chlorophyll

Question 25

physical defence responses in plants

Answer 25

• cellulose cell walls
• tough waxy cuticle on leaves
• layers of dead cells around stem which fall off (bark)

Question 26

chemical defence responses in plants

Answer 26

• antibacterial chemicals
• poisons to deter herbivores

Question 27

mechanical adaptations in plants

Answer 27

• thorns and hair deter animals
• leaves which droop or curl when touched
• mimicry to trick animals

Question 28

why can monoclonal antibodies not be consumed oraly

Answer 28

they are proteins so would be broken down into amino acids by protease

Question 29

why has there been an increase in resistant strains of bacteria

Answer 29

• there are less non resistant strains as they have been killed by antibiotics so there is less competition
• theres been an overuse of antibiotics / antibiotics have been prescribed for mild infections