topic 3- infection and response

Created by

DYLAN ROBERTS

Cards (72)

what is a pathogen 
a pathogen is a microorganism that enters your body and causes disease. they are communicable (easily spread). Both plants and animals can be infected by pathogens
bacteria are very small living cells
how big is bacteria
about 1/100th the size of your body cells
bacteria produces toxins that damage your cells and tissue
viruses are not cells
how big are viruses
about 1/100th of the size of a bacterium
viruses live inside your cells and replicate themselves using the cells machinery to produce many copies of themselves. the cell will usually then burst, releasing all new viruses
protists are single celled eukaryotes
what is a parasite
a form of a protist. that lives on or inside another organism and can cause them damage. they are often transferred to the organism by a vector, which doesn't get the disease itself. for example, an insect that carries the protist
fungi come in different shapes, some are single celled and others have a body which is made up of hyphae
what is a hyphae
a thread like structure
how does a hyphae cause disease
they can grow and penetrate human skin and the surface of plants, they than produce spores which spread the disease to other plants and animals
how can pathogens spread
water- drinking or bathing in dirty water
air- carried in the air then breathed in, some are carried in the air in droplets produced when you cough or sneeze
direct contact- touching something that someone infected has touched
what type of disease is measles
a viral disease
how are measles spread
by droplets from an infected persons sneeze or cough
what do people with measles develop
a red skin rash, and they will show a sign of fever. It is very serious and can be fatal if complications
most people are vaccinated against measles at a young age
what is HIV 
a virus that is spread by sexual contact or by exchanging body fluids such as blood, by sharing needs when taking drugs.
what are symptoms of HIV 
flu like symptoms for the first weeks, usually there are no symptoms for the first couple years.
how do we stop HIV
antiretroviral drugs that stop the virus replicating in the body
what does the HIV do
attack your immune system, if it damages the immune system badly, your immune system will struggle coping with other infections or cancers. at this stage it can be known as AIDS
what is tobacco mosaic virus 
a virus that affects many species of plants. it causes a mosaic pattern on the leaves of the plant and parts of the leaves become discoloured.
this decolouration means the plant will find it harder to carry out photosynthesis, so the virus will also affect growth
what are rose black spots
a fungus that causes purple or black spots to develop on the leaves of rose plants, the leaves can then turn yellow and fall off. this means less photosynthesis will happen, and the plant will struggle to grow
how are rose black spots spread 
through the environment in water or by the wind
how do gardeners treat rose black spots
using fungicides and by stripping the plant of its affected leaves, these leaves need to be destroyed so that the fungus cannot spread to other rose plants
what is malaria  
a disease caused by a protist, part of the malarial protists life cycle takes place inside the mosquito, therefore the mosquito is a vector
what are symptoms of malaria
repeating episodes of fever and can be fatal
how do we stop the spread of mosquitos
stopping mosquitos from breeding or using a mosquito net
what are 2 bacterial diseases
salmonella and gonorrhoea
what does salmonella cause
food poising
what are symptoms of salmonella
fever, stomach cramps, vomiting and diarrhoea
what are the symptoms of salmonella caused by
toxins that are produced by bacteria
how do we control the spread of salmonella in the uk
most poultry (e.g. chickens) are given a vaccination against salmonella
what is gonorrhoea 
a sexually transmitted disease (STD)
how is gonorrhoea passed on
by sexual contact
what is gonorrhoea caused by
bacteria
what are symptoms of gonorrhoea
pain when urinating or a thick yellow discharge from private area
how do we prevent the spread of gonorrhoea
people are treated with antibiotics and should use barrier methods of contraception, for example condoms
what are 3 examples of viral diseases
measles
HIV
tobacco mosaic virus
what is an example of a fungal disease
rose black spots