response to disease

Question 1

what do non specific defences do

Answer 1

prevent the entry of pathogens into the body (in the blood)

Question 2

what makes the skin act as a barrier give 2 things

Answer 2

platelets are involved in clotting blood which dries and forms a scab, the scab acts as a barrier
produces oil (sebum) which repels pathogens

Question 3

what does the respiratory system do
-mucus
-stomach
-eyes

Answer 3

produces mucus (nose trachea + bronchi) mucus traps pathogens and ciliated cells waft the mucus to the back of the throat to be swallowed
stomach contains hydrochloric acid which kills pathogens
eyes - produce tears which contain enzymes to kill bacteria

Question 4

when does specific defense occur

Answer 4

they occur if a pathogen has entered your body, it uses the immune system which involves white blood cells

Question 5

what do white blood cells do for specific defense

Answer 5

they can produce and release anti-toxins to neutralise the toxins released from bacteria. white blood cells can engulf and digest pathogens this is called phagocytosis

Question 6

what do wbcs do for specific defense

Answer 6

pathogens have a unique molecule on their surface called antigens. white blood cells produce antibodies specific to the antigen, they are complementary in shape. the antibodies bind to the antigens and destroy the pathogen

Question 7

what are antibodies such as penicillin used to treat

Answer 7

used to treat bacterial diseases by killing bacteria that is inside the body

Question 8

what are antibodies not used to treat and why

Answer 8

antibodies are not used to treat viral diseases this is because viruses invade host cells in order to reproduce and replicate, therefore antibiotics would cause damage to our cells and tissues

Question 9

what is a big problem of antibiotics

Answer 9

one problem of antibiotics is its the emergence of strains of bacteria that are resistant to the antibiotics.

Question 10

what are painkillers and what r they used to treat and what do they not do

Answer 10

painkillers are another type of medicine that are used to treat the symptoms, painkillers do not kill any pathogens

Question 11

what is an antibiotic how does it differ to a painkiller

Answer 11

an antibiotic is medicine that helps cure bacterial diseases by killing the bacteria, painkillers dont kill any pathogens and treat symptoms

Question 12

why have fungi evolved to produce anitbiotics?

Answer 12

Fungi naturally produce antibiotics to kill or inhibit the growth of bacteria, limiting their competition in the natural environment

Question 13

where have most drugs come from

Answer 13

plants and micro-organisms

Question 14

where do these following drugs come from and what r they
digitalis
aspirin
penicillin

Answer 14

digitalis - heart drug - foxgloves
aspirin - painkiller - willow
penicillin - antibiotic - comes from penicillin mould - mould discovered by sir alexander flemming

Question 15

what are most new drugs synthesised by

Answer 15

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 16

what is meant by antibiotic resistant bacteria

Answer 16

bacteria that is not killed and will continue to grow around the antibiotic disc ( no zone of inhibition)

Question 17

what is meant by non resistant bacteria

Answer 17

bacteria that will be killed and will not continue to grow around the anitbiotic disc called the zone of inhibition

Question 18

how do u calculate the area of zone of inhibition

Answer 18

pierrrsquared

Question 19

how to calculate percentage change e.g.
the number of robins in a woodland area is counted over two different months. In December 15 robins were counted. In January 23 robins were counted. What is the percentage increase of robins in the woodland?

Answer 19

work out the difference between the two numbers being compared.
divide the increase by the original number and multiply the answer by 100.
in summary: percentage increase = increase ÷ original number × 100.
the difference between the two numbers is 8
8 ÷ 15 × 100 = 53.3
the percentage increase of robins found in the woodland is: 53.3%

Question 20

what r vaccines used to do

Answer 20

theyre used to provide immunity for pathogens

Question 21

what does MMR stand for

Answer 21

measles,mumps and rubella

Question 22

how do vaccines work

Answer 22

small amounts of a dead or inactive form of the pathogen is injected into the body
the dead pathogen has antigens on its surface. this triggers white blood cells to produce specificic complementary antibodies
memory cells r produced they remain in blood stream. on re - exposure memory cells allow specific antibodies to be made faster ,sooner, to a higher concentration and remain in the bloodstream for longer
the pathogen is killed before the person presents w any symptoms. person now immune to that particular pathogen

Question 23

many communicable diseases that were once common are now rare

Question 24

whats herd immunity

Answer 24

if most population are vaccinated (immune) and dont become ill its unlikely that those who r unvaccinated will be exposed to the pathogen this is called herd immunity

Question 25

what r negatives of vaccines

Answer 25

dont always work and provide immunity
some can have bad reaction + side effects

Question 26

what does MCA stand for and what r they made of

Answer 26

MCA - monoclonal antibodies are made from a single clone of cells

Question 27

what are monoclonal antibodies produced by

Answer 27

stimulating mouse lymphocytes ( white blood cells) to make particular antibody
the lymphocytes combine w a specific tumour cell this makes a hybridoma cell
hybridoma cell can divide and make antibody
clone a hybridoma lots of times to make identical cells that make the same antibody

Question 28

what are pre-clincial carried out in the lab on

Answer 28

theyre carried out in the lab on cells,tissues or live animals

Question 29

what r 3 things pre clinical trials tested for

Answer 29

efficacy - checking the drug is working
dosage - the concentration of the drug and how it should be given
toxicity - how harmful the drug is

Question 30

what are the steps of clinical trials

Answer 30

the drug is given to healthy volunteers at very low doses
monitoring safety + any side effects
if the drug is safe it then enters a double blind clinical trials

Question 31

what is a double blind clinical trial

Answer 31

patients with the disease are randomly assigned into one of two groups 1/2 are given the new drug then the other half is given a placebo (substance like the new drug but does nothing this is given to avoid the psychological aspect of the patients thinking they’re getting better)

Question 32

why do we do double blind clinical trials

Answer 32

to avoid a psychological aspect of patients thinking they’re getting better,
neither the patients or doctor who know who’s been given the danger placebo - to remove bias

Question 33

why are results peer reviewed

Answer 33

they’re peer reviewed to prevent false claims

Question 34

what’s the aim of the clinical trial

Answer 34

aim is to monitor the efficacy + determine optimum dosage

Question 34

what are monoclonal antibodies produced from

Answer 34

monoclonal antibodies are produced from lots of clones of a single white blood cell ( a b-lymphocytes)

Question 35

what are 3 uses of monoclonal antibodies

Answer 35

cancer treatment , loading specific molecules in research, measuring levels of substances in blood or urine e.g. pathogens, hormones and other chemicals

Question 36

describe the process of making monoclonal antibodies

Answer 36

.mouse is injected w a specific antigen to make specific antibodies
.the mouse’s b-lymphocytes/B cells produce the specific antibodies
.the mouses b-lymphocytes are fused w a tumour cell to form a hybridoma cell
.select aa hybridoma cell that is producing the specific antigen of interest
. the hybridoma cell is then cloned in a lab as it divides by mitosis to produce identical cells, all producing the same antibodies (monoclonal antibodies)
. the antibodies are collected and purified

Question 37

advantages and disadvantages of monoclonal antibodies

Answer 37

advantages - used in cancer treatment: has fewer side effects than standard chemotherapy or radiotherapy
disadvantages - not as widely used as it creates more side effects than suspected

Question 38

how are monclonal antibodies used in research

Answer 38

in research to locate or identify specific molecules in a cell or tissue by binding to them w a fluorescent dye

Question 39

how are monoclonal antibodies used to treat some diseases

Answer 39

to treat some diseases e.g. cancer by attaching a radioactive substance/toxin/drug to the monoclonal antibodies. the monoclonal antibody will attach to the antigens on the target cell/cancer cell. the radioactive substance/toxin/drug will stop them from growing and dividing

Question 40

cwho was penicillin discovered by

Answer 40

Alexander Flemming

Question 41

what do plants defend themselves again

Answer 41

pathogens and herbirory

Question 42

3 defences

how can/do plants defend themselves

Answer 42

physical defences - cellulose cell walls, thick waxy cuticle on leaves
chemical defences - poisions which defer away herbivores + less damage to plant, antibacterial chemicals - kill pathogens
mechanical defences - thorns/spikes/hairs - deters away herbivores, mimicry

Question 43

how can pathogens spread and give examples

Answer 43

water - some pathogens can be picked up by drinking or bathing in dirty water e.g. cholera is a bacterial infections thats spread by drinking water contaminated w the diarrhoea of other sufferers
air - pathogens can be carried in the air and can be breathed in e.g. the influenza virus that causes flu is spread in the air in droplets produced when u cough or sneeze
direct contact - some pathogens can be picked up by touching contaminated surfaces including the skin e.g. athletes foot is a fungus which makes skin itch and flake off most commonly spread by touching same things as an infected person

Question 44

what r the 3 viral diseases + hows it spread

Answer 44

measles - spread through droplets from an infected person’s sneeze or cough
HIV - spread by sexual contact or by exchanging bodily fluids such as blood
tobacco mosaic virus (TMV) is virus that affects many species of plants e.g. tomatoes

Question 45

give symptoms of measles and HIV

Answer 45

measles - ppl often develop a red skin rash and show signs of fever (high temp)
HIV - causes flu like symptoms for a few weeks then usually person doesn’t then experience any symptoms for several years

Question 46

what type of drugs r used in the early stages of HIV and how can/do they stop it

Answer 46

HIV can be controlled w antiretroviral drugsthese stop the virus replicating in the body

Question 47

explain why growth is affected in a plant infected w the tobacco mosaic virus

Answer 47

in plants w TMV parts of the leaves become discoloured this means that the plant c an’t carry out photosynthesis aswell, as growth is affected, photosynthesis produces glucose which is one thing used for growth

Question 48

what is malaria caused by

Answer 48

malarias caused by a protist