communicable diseases Flashcards
what are pathogens
microorganisms which cause infectious diseases
why cant viruses reproduce on their own
they can only reproduce in a host cell
how do viruses reproduce
first the virus invades the host cell and then reproduces in it
how does virus reproduction affect cells
virus reproduction in cells is very damaging to the cells
if the virus leaves the cell what can happen
the cell can burst and die
what kind of cell is fungi
(2 points)
eukaryotic and can be unicellular or multicellular
what structures do fungi have and how does this cause disease
fungi have long threadlike structures called hyphae which can penetrate human skin or spread over plants
how do more fungi generate
fungi can produce spores and grow into more fungi
what kind of cell is protist
2 points
eukaryotic, uni or multicellular
how do protists spread disease
they are transported by vectors which carry the disease and spread it to other organisms
vectors do not_
vectors do not receive the disease itself
what are some protists
parasites
what kind of cell is bacteria
prokaryotic
how does bacteria cause illness
bacteria reproduces rapidly
they release harmful toxins which damage tissues and make us feel ill
how can pathogens be spread
in the air
water droplets in air from coughing or sneezing
in water like cholera
direct contact eg needles
sexual intercourse
hygiene
what kind of pathogen is measles
virus
what are the 2 symptoms of measles
- a fever
- a red rash after 3 days on the body
how is measles spread
when a person inhales water droplets that an affected person spread through coughing or sneezing
what can happen is serious cases of measles
complications such as damaged breathing system or brain damage
how is measles prevented
children are usually vaccinated against measles when they’re young
what are the symtpoms of hiv and what does this signify
a flu-like illness that disappears after 2 weeks
the virus is attacking the patient’s immune system at this point
what kind of pathogen is hiv
virus
what happens overtime with hiv
the immune system becomes damaged so much that it cant even fight off normal infectons (late stage)
what happens to the patient after reaching late stage HIV
they may get infections like tb or even develop cancer
this is known as aids which is often fatal
how is hiv spread
through exchanging fluids
what drug is used to control hiv
how do these work
3 points
antiretroval drugs
they stop the virus from multiplying in the patient and the virus wont damage the patients immune system
if patients take these they dont develop aids and can have a normal life expectancy
what is significant about antiretrovals
antiretrovals is not a cure, patients must take this for the rest of their life
what pathogen causes salmonella
bacteria
how is salmonella spread
through eating infected food
food that was prepared unhygienically
the bacteria _ _
which causes symptoms:
(4)
the bacteria secretes toxins causing symptoms: fever, abdominal cramps, vomiting, diarrhoea
where is salmonella sometimes found
in poultry like chicken
how is salmonella prevented in the uk
all chickens in the uk are vaccinated against salmonella, controlling spread of the disease
what kind of pathogen is gonorrhoea
bacteria
what are symptoms of gonorrhoea (2)
thick yellow or green discharge from penis or vagina
pain while urinating
how was gonorrhoea treated before and why doesnt it work anymore
with penicillin but gonorrhoea became antibiotic resistant overtime
how can the spread of gonorrhoea be controlled
by using condoms, a barrier protection
if you have unprotected sex what should you do and why
test yourself for stds/stis so you can be treated before passing it on
what kind of pathogen is malaria
protist
what are symptoms of malaria
repeated bouts of fever
how can we prevent the spread of malaria
by eradicating the mosquito
how does the mosquito spread malaria
it is a vector, carrying the disease
how can we eradicate mosquitoes
by stoping them from breeding
where do mosquitos breed and how do we get rid of this
2 ways
mosquitos breed in still water so we need to drain them
or we can spray insecticide around the area to directly kill
what 2 ways can we protect ourselves from mosquitos
by preventing bites - sleeping under a net
spraying inseticide on the net so mosqusitos landing on them die
what causes tobacco mosaic virus - tmv and what does it affect
viruses, it affects plants like tomatos
what happens when a plant get tmv - slowing down _
the leaves become discoloured and frm a mosaic pattern slowing down photosynthesis
what does rose black spot affect and and what pathogen is it
its fungal and affects plants
what happens to plants after getting rose black spot
3 points
leaves gain purple or black spots
leaves often turn yellow and fall ff
the rate of photosynthesis is reduced and therefore the rate of growth
what is rbs spread in
water or wind
