B6.3 - health Flashcards
what is health
- physical social and mental well being
communicable diseases
caused by infections eg measles and HIV
pathogens
cause infectious diseases
- bacteria
- viruses
- fungi
- protists
viruses
- smallest type of microbe
- viruses invade our cells multiply inside them and burst out of them - destroying our cells
- only live and reproduce inside cells of living organisms
- viruses are not cells - made up of protein and genetic material
viruses eg
influenza
HIV
tobacco mosaic virus
bacteria
- mostly harmless - some pathogens
- single celles - no nucleus
- don’t have to invade cells to live
- produce toxins that cause disease symptoms
bacteria eg
tuberculosis
cholera
fungi
- mostly harmless but some pathogens
- some multicellular
- make fine threads (HYPHAE) which can invade cells and absorb nutrients from them causing symptoms
- others are single celled
- can live on decaying substances or living tissue
fungi eg
athletes foot
barley powdery mildew
protists
- single celled eg amoeba
- some cause disease
- are larger than viruses / bacteria
- feed by absorbing nutrients from surroundings
athletes foot
- spread by fungus (direct / indirect contact)
- cracked / flaking / itchy skin
- treated by anti fungal cream
tobacco mosaic virus
- by a virus (contact)
- mottled / discoloured leaves
- affects chloroplast formation + growth
- plants removed and burnt to prevent spread
cholera
- caused by bacteria in dirty water
- diarrhoea / dehydration
- treated by boiling water / sterilising treatment reduces spread
influenza
- virus carried in cough / sneeze droplets
barley powdery mildew
- cause by fungal disease - and spores in wind
- white powdery spots on leaves
- affects photosynthesis - decreases yield
- treated by spraying fungicides
salmonella
- found in raw milk/eggs and unpasteurised milk
- stomach pains / diarrhoea/ vomiting
- decrease spread by cooking food thoroughly
crown hall disease
- bacterium in soil - enters through wound
- tumours grow which cut off water flow
- infected plants removed and destroyed and area left for years so bacteria dies
malaria
- protozoan is carried by mosquitoes - pass on when feeing on blood
- fever / can be fatal
- be vaccinated and take medication
HIV
- exchanging bodily fluids eg blood/ semen spread it
- attacks white blood cells weakening immune system
- AIDs is final stage when body can’t fight off infection
reason for washing hands before cooking
stops bacteria from skin getting onto food
reason for keeping raw and cooked food separate
stop bacteria on raw food getting onto cooked food
pathogen that causes malaria
protist - plasmodium
- single celled organism that spends some life in mosquitoes and some in humans
prevention of malaria
- use drug to kill protist
- avoid being bitten
- mosquito control
aphid infection
- mottled / discoloured leaves + low growth
- aphids feeding on sap cause it
- treatment using insecticides or removing aphids
nitrate deficiency
- stunted growth
- due to not enough nitrates in soil
- add minerals to soil to cure
magnesium deficiency
- chlorosis(yellow leaves)
- due to not enough magnesium in soil
- add magnesium to soil
apple scan
disease in fruits with stones eg plums
- caused by a fungus
- fruit goes brown
blossom end rot
- disease found in tomatoes
- sunken brown leathery spots on fruit
brown rot
- sunken spots with velvety spores on leaves and fruit
club rot
- found in plants of cabbage family
- caused by fungus in soil
- plants show mineral deficiency
plant physical defences
- cellulose (cell wall) - prevents pathogens entering cell
- tough waxy cuticle - prevents pathogens entering epidermis
- layers of dead cells around stem - prevent entry of pathogens
plant chemical defences
- produces antibacterial chemicals - increase when plant is attacked
- produce poisons - taste bad so deter herbivores
plant mechanical defences
- thorns - impair insects and prevent eggs being laid - deter grazing herbivores - prevent larvae feeding
- dropping / curling leaves when touched
- mimicry - trick animals into not feeding/laying eggs
financial cost of smoking
cost of cigarette,
loss of income
reduce workforce
burden of health care costs on the economy
stent cell
A small
mesh tube that opens a narrowed cornory artery to the heart to give it O2
faults in heart valves
nto open fully
leak
natural pacemaker
sinus node generated heartbeat
cancer
A disease resulting from changes in cells that lead to their uncontrolled growth and division
a tumour can spread by blood, to other body part and cause a secondary tumour
why is cancer dangerous
it can cause blockages in blood supplies.
It’s harder to treat when it’s in other tissues as it causes more blockages and affects more organs.
what woudk happen if a detached cancer cell remained in the capillary
would burst and cells reliant on this will die
why hard to fight cancer
caused by own cells
immune system doenst recognise threat
