Topic 3- Infection and Response. Flashcards
what are pathogens?
they are microorganisms that enter the body and cause disease.
what do pathogens cause?
they cause communicable (infectious) diseases.
what can be infected by pathogens?
both plants and animals can be infected.
what are the four main types of pathogens?
- bacteria.
- viruses.
- protists.
- fungi.
what are the ways that pathogens can spread?
- water- drinking or bathing in dirty water.
- air- can be carried in the air and can be breathed in. some can be carried in droplets made when you sneeze or cough.
- direct contact- can be picked up by touching surfaces they are on (e.g: the skin).
how can the spread of diseases be reduced or prevented?
- being hygienic- washing hands.
- destroying vectors - vectors are organisms that spread diseases.
- isolation infected individuals- keep them away from other people.
- vaccination- can stop people and animals from getting a communicable disease.
what are bacteria?
very small living cells.
how fast can bacteria reproduce?
can reproduce rapidly inside your body.
how does bacteria make you feel ill?
they produce toxins which is poisons- they can damage your cells and tissues.
what are the two diseases that are bacterial diseases?
- salmonella.
- gonorrhoea.
what is salmonella?
- it is a type of bacteria that causes food poisoning.
- people can suffer from fever, stomach cramps, vomiting and diarrhoea.
- these are caused by toxins from the bacteria.
- you can get it… if food is already containing it or it’s been cooked at a place where’s t contains it.
- in ik- poultry (chickens/turkeys) are given vaccinations.
what is gonorrhoea?
- it is caused by a bacteria.
- it is a STD.
- they are passed on by sexual contact.
- pain with they urinate. a thick yellow/green discharge from the vagina/penis.
- used to be treated with antibiotics (penicillin) now it is resistant to penicillin- new strains.
- to stop the spread- treat win other antibiotics or use barrier methods.
are viruses cells or not?
they are not cells.
how do viruses reproduce?
they reproduce rapidly.
where do viruses live?
inside your cells.
what do viruses do inside your cells?
they make lots of copies of themselves.
what happens to the cell after they make lots of copies of themselves?
the cells usually burst which releases all the new viruses.
what makes you ill?
the cell damage.
what viruses can cause different diseases?
- measles.
- HIV.
- tobacco mosaic virus.
what is measles?
it is spread by droplets form an infected person’s sneeze or cough. they develop a red skin rash and have symptoms of a fever. it can be very serious as people can die if they are any complications. therefore a lot of people are vaccinated against measles when they are young.
what is HIV?
it is spread by sexual contact or by exchanging bodily fluids. this can happen when people share needles when taking drugs. for a few weeks HIV causes flu-like-symptoms. it is controlled by antiretroviral drugs. this stops virus copying itself in the body. if not controlled it attacks the immune system. if immune sytem damaged then it cannot cope with other infections- this stage is called late HIV infection or AIDS.
what is tobacco mosaic virus?
it is a virus that affects many species of plants. (e.g:tomatoes). causes part of the leaves to become discoloured which gives them a mosaic pattern. the discoloured leaves have less chlorophyll to absorb light. this means less photosynthesis happens in the leaves so plant can’t make enough food to grow.
what is a rode black spot?
it is a fungal disease. the fungus causes purple/black spots on the leaves of rose plants. the leaves turn yellow and drop off. this means less photosynthesis can happen so less growing. it is spread by water or the wind. gardeners can treat this using fungicides or strip the affected leaves off the plant. these leaves need to be destroyed.
what is malaria causes by?
a protist.
where does part of the protist’s life cycle take place?
takes place inside the mosquito.