Infection and response Flashcards
(16 cards)
what are pathogens?
microorganisms that enter the body and cause disease. - cause communicable diseases
what are bacteria, and how can they make you ill?
very small cells which can reproduce rapidly inside your body, they can make you feel ill by producing toxins that damage your cells and tissues.
what are viruses and how do they make you ill?
they aren’t cells. they are tiny. they can reproduce rapidly inside your body, they live inside your cells and replicate themselves and produce copies. the cell will usually burst releasing all the new viruses. the cell damage is what makes you feel ill.
what are protists, and how do they make you ill?
single celled eukaryotes. some are parasitic, they use humans and animals as their hosts (live on and inside, causing damage)
how can pathogens be spread?
water - drinking or bathing in dirty water
air - carried or breathed in, coughing or sneezing
direct contact - touching contaminated surfaces, including the skin
measles - what type of disease and what it is
viral disease. spread by droplet from an infected person, sneeze or cough. People with measles develop a red skin rash and they’ll show signs of a fever. Most people are vaccinated against it when they young.
HIV and what type of disease it is
a virus. spread by sexual contact or by exchanging bodily fluid such as blood. This can happen when people share needles when taking drugs HIV. initially causes flu like symptoms for a few weeks. Usually the person doesn’t then experience any symptoms for several years during this time HIV can be controlled with antiretroviral drugs. this stops the virus replicating in the body. the virus attacks the immune cells. if the bodies immune system is badly damaged, It can’t cope with other infections or cancers. At this stage. The virus is known as a late stage HIV infection or aids.
Tobacco mosaic virus
tobacco mosaic virus is a virus that infects many species of plant. It causes a mosaic pattern on the leaves of the plant. parts of the leaves become discoloured. The discolouration means a plant can’t carry out photosynthesis as well so the virus affects growth
rose black spot - what kind of disease
fungal disease . cause purple or black spots to develop on the leaves of rose plants. less photosynthesis happens. it spreads through the environment by water or by the wind, gardeners can treat the disease using fungicides and by stripping the plant of its affected leaves.
fungi
can either be single celled or have a body made of hyphae. can produce spores which can be spread to other organisms.
malaria - what type of disease
caused by a protist pathogen. the symptoms are fevers and shaking. protist mosquito in which the protists reproduce sexually. When the mosquito punctures the skin to feed on blood the protists enter the human blood stream via their saliva. repeating episodes of fever.
- stop mosquitos from breeding, mosquito net
salmonella - what type of disease
bacterial disease. food poisoning. The symptoms of fever, stomach cramps, vomiting, diarrhoea. these bacteria can be found in raw meat and eggs, unhygienic conditions.
most poultry is given a vaccination against salmonella, raw meat away, wash hands and surface properly, cook food properly
gonorrhoea - what type of disease
bacterial disease. sexually transmitted disease spread through unprotected sexual contact. The symptoms are thick, yellow or green discharge from the vagina or penis. pain when urinating.
prevented by using contraception and antibiotics. used to be treated with penicillin, but many resistant strains are developing
how can the spread of disease be reduced or prevented
being hygienic, destroying vectors, isolating individuals that are infected, and vaccination
body’s defence systems -
the skin - acts as a physical barrier, secretes anti microbial substances which kill pathogens
hairs and mucus in your nose - trap particles that could contain pathogens
the trachea and bronchi - secrete mucus in order to trap pathogens
stomach - produces hydrochloric acid that kills pathogens
how your immune system can protect you: 3 ways
phagocytes: white blood cells, such as phagocytes l indigo foreign cells and digest them
producing antibodies: every invading pathogen has unique molecules called antigens on its surface. When some types of white blood cells come across a foreign antigen, they will start to produce proteins called antibodies to look onto the invading cells so that they can be found and destroyed by other white cells. The antibodies produced a specific to that type of antigen so they won’t look onto any others. Antibodies are then produced rapidly and carried around the body to find all the similar bacteria or viruses. If the person is infected with the same pathogen again, the white blood cells will rapidly produce the antibodies to kill it. The person is naturally immune to that pathogen and won’t get ill
anti toxins - these counteract toxins produced by the invading bacteria
