Pathogens and immunity

microorganism that cause disease

kwnon as infection

passed from one person to another

transmissible diseases

direct transmission

between an infected person and an undifected one

person who has the parhogen: HOST

contagious diseases

AIDS (hiv)

fungus

indirect transmission

Through the respiratory passages

viruses are propelled into the air in tiny droplets pf moisture

speaks, coughs, sneezes

breathe the droplets, become infected

touch a surface and then put them into the face

In food or water

through the alimentary canal

salmonella

food poisoning

fresh food should be washed

cooking destroys bacteria

transmityed in water

poliomyelitis

cholera

By vectors

organism that carries a pathogen from a host to another

anopheles mosquitoes

malaria

dogs, skunks, raccoons, bats

rabies

female mosquitoes

plasmodium

natural defences

Mechanical barriers

skin

has keratin, that is difficult to penetrate

when it is cut

blood clots seam the wound

Chemical barriers

sticky mucus

cilia sweep the mucus back up to the throat

hydrochloric acud is secreted

the ones that go through are destroyed by White blood cells

by phagocytosis

by producing antibodies

vaccination

Food hygiene

keep own bacteria and viruses away from food

wash hands

hair out of food

don't cough or sneeze over food

keep animals away from food

cover food

don't keep foods at room temperature for long periods

keep food in fridge

cooking at high temperature

keep raw meat away from other foods

bacteria might get onto other foods

Personal hygiene

keep body clean

washed the skin regularly

evaporation of water from sweat

Brush the teeth every day and use mouthwash

Waste disposal

waste food, cardboard, paper packaging, bottles,
papers, plastic bags, old tyres

Bacteria breed in the waste food

Dangerous chemical seep out of the rubbish

Produced methane

can cause explosions

can be used as fuel

Sewage treatment

waste liquid from houses, industries, towns and cities

mostly water

includes: urine, faeces, toilet paper, detargents, oil

can harm people and the environment

untreated sewage

raw sewage

contains bacteria that are likely to be pathogens

if it gets into the mouth, you become ill

lymphocytes produce antibodies to destroy pathogens

these are only produce when a pathogen is detected

when it enters the body, it meets with lymphocytes

the lymphocytes will start to divide by mitosis making a clone of lymphocytes that will secret antibodies to destroy the pathogen

while the lymphocytes do this, the pathogens breeds making you ill

inmune response

Antibodies

is a protein molecule that its shape fits right into the antigen to destroy it

the antibodies alert the phagocytes do that they would come and kill them

the antibodies sart off a series of reactions in blood that produce enzymes to digest phatogens

Memory cells

when the lymphocyte clones itself, it goes to the blood or other parts of the body

memory cells

if the same patjogen gets in the body the memory cells will be ready and kill it before it does any harm

inmune

Vaccination

inmunise people against diseases

contains weakened or dead viruses that normally causes diseases

when it enters the body, it will be recognise by lymphocytes that makes antibodies that lock with the antigens

also making memory cells to have long-term inmunity

Avtive and passive immunity

Active inmunity

make your own antibodies and memory cells

by having the diseases and getting over it

vaccinated

long-lasting

Pasive inmunity

given antibodies by another organism

injected with antibodies made by another organism

lasts for a short time

auto-immune diseases

lymphocytes can confuse our own cells with pathogens

type 1 diabetes

in some people their inmune system attacks the betas cells, in the pancreas, and destroys them

stops producing insulin