topic 3 - infections and response Flashcards
name the types of pathogens
virus
protists
bacteria
fungi
describe a virus
- very tiny
- invade host cells and makes copies of itself this causes the cell to burst and release all the copies into the bloodstream
- viruses live and reproduce inside the cell causing damage and destruction of the cells making us feel ill
how does a virus work
- make many copies of itself
- which causes the cell to burst and release all the copies into the bloodstream
- where is will damage the cell and make us ill
describe bacteria
- small living cells
- they multiply very quickly through dividing by a process called binary fission
- produces toxins that damage the cells
how do a bacteria work
- they multiply quickly by binary fission
- and produce toxins that damage the cells
describe protists
- single celled eukaryotic organism often transferred to the host by vector
- meaning they use animals and human as their host
- causing damage to the cells
describe fungi
they can either be single celled or have a body made of hyphae ( thread like structure )
they produce spores which can be spread to other organisms
name the ways they are spread:
by air/droplet infections
by direct contact
by water
by vectors
explain how air can spread diseases
pathogens can be carried in the air and inhaled by other organisms
for example, pathogens released by droplet infection eg. sneezing, coughing which would be inhaled by another organism
explain how water can spread diseases
pathogens can contaminate water supplies so organism drinking this contaminated water can be infected by pathogens
explain how direct contact can spread diseases
pathogens live on surfaces and touching these contaminated surfaces could spread to other organisms
explain how vectors can spread diseases
mosquitoes, fleas, ticks can carry infected pathogens which can be transferred to others
name ways of by limiting the spread of the
pathogens.
improving hygiene
vaccinations
destroying vectors
isolation
how does vaccination limit the spread of pathogens
make people immune to infections this reduces the spread of disease
how does hygiene limit the spread of pathogens
Improving hygiene: Hand washing, using disinfectants, isolating raw meat, using tissues
and handkerchiefs when sneezing
how does destroying vectors limit the spread of pathogens
Using pesticides or insecticides and removing their habitat or using mosquito nets
how does isolation limit the spread of pathogens
isolating infected individuals prevent them from passing it on to others
name the viral diseases
measles
HIV
tobacco mosaic
measles
type - a viral disease
symptoms - fever, red skin rash, blindness, brain damage
spread - droplet infections
prevented - vaccination -childhood vaccination
treatment - no cure
HIV
type - a viral disease
symptoms- mild flu-like illness then the virus attacks the immune system and leads to AIDS
spread - direct sexual contact or exchange in body fluids such as blood or mother to child in breast milk
prevented - barrier methods, not sharing needles, screening blood used for transfusion
The development to AIDS- Use of antiretroviral drugs
treatment - no cure
tobacco mosaic
type - viral diseases
symptoms - discolouration on leaves , cannot photosynthesise ,reduction of the yield
prevented - good field hygiene , pest control , growing TMV-resistant strains.
spread-Contact between diseased plants and healthy plants, insects act as vectors.
name all bacterial diseases
salmonella
gonorrhoea
rose black spot
salmonella
type - bacterial disease
symptoms - Fever, stomach cramps, vomiting, diarrhoea (all caused by the toxins they secrete).
spread - found on uncooked meat and unhygienic conditions
prevented :
- Poultry are vaccinated against Salmonella,
- keeping raw meat away from cooked food
- avoid washing it,
- wash hands and surfaces when handling it, cook food thoroughly.
gonorrhoea
type - bacterial disease
Symptoms: Thick yellow or green discharge from the private part pain when urinating.
spread - sexually transmitted disease spread through unprotected sexual contact.
prevented -By using contraception such as condoms and antibiotics
treatment - penicillin or antibiotics
name fungal diseases
rose black spot
rose blackspot
type - fungal disease
symptoms - purple/black spots on leaves , reduces photosynthesis , damage leaves
spread - The spores of the fungus are spread in water (rain) of by wind
prevented- burning the infected area , using fungicides
name protists diseases
malaria
malaria
type - protist disease (caused by protist pathogens that enter red blood cells and damage them)
symptoms - fever / shaking
spread - by the bite of female mosquitoes
prevented - mosquito nets / Using insecticide,
Human Defence System - The non-specific defence system name 5
the skin the nose the trachea and bronchi the stomach the tears
The non-specific defence system - skin
-acts as a physical, waterproof barrier
-It produces antimicrobial secretions to kill pathogens
-Good microorganisms known as skin flora compete with the bad microorganisms for
space and nutrients
The non-specific defence system - nose
contains hair and mucus which traps particles from entering your lungs
The non-specific defence system - trachea and bronchi
the trachea and bronchi are lined with cilia (hair-like -substance ) which wafts the mucus up to the mouth where it should be swallowed
The non-specific defence system - stomach
Produces hydrochloric acid that kills any pathogens
The non-specific defence system - tears
contains enzymes that kill pathogens
The specific immune system what are they
white blood cell in which act in 3 different ways
antibodies
antitoxins
phagocytosis
Phagocytosis
the white blood cells engulf and digest them which destroys them meaning they can no longer make you feel ill.
antibodies are also known as
lymphocytes
lymphocytes - antibodies
each pathogen has an antigen on their surface which a specific complementary antibody can bind to. it locks onto the invading pathogen. if the same pathogen infects the organism the white blood cell will produce the specific complementary antibodies at a faster rate.
antitoxins
counteracts toxins released by pathogens pathogen by binding to them.
how does the immune system attack the pathogens
the immune system protects us from pathogens, the most important part of the immune system is the white blood cell can act in 3 different ways. phagocytosis is when the white blood cells engulf and digest the pathogens this will destroy them meaning you no longer feel ill. white blood cells can also produce antibodies which bind to an antigen and would lock onto the invading pathogens. antibodies are a specific complementary shape so if the person is infected with the same pathogen the white blood cells will rapidly and in higher concentration produce the specific
complementary antibodies at a faster rate. lastly, the white blood cells also produce antitoxins which counteract toxins released by the pathogens by binding to them.
define vaccination
vaccination involves dead or inactive pathogen injected into the blood, this leads to antibodies being produced which bind to the pathogens and destroy them . memory cells are left behind in the blood so if the pathogen re-enters the white blood cells can produce antibodies rapidly
define herd immunity
a large proportion of the population is immune to pathogens the spread of the pathogens is reduced
Advantages of vaccination
have eradicated many diseases
protection
Disadvantages of vaccination
not always effective in providing immunity.
Bad reactions
define health
a state of physical and mental well being
define non-communicable disease
is not caused by pathogens and cannot be passed on
define communicable disease
infectious diseases caused by pathogens and can be passed from one person to another
Antibiotics
kills bacterial pathogens inside the body
what can’t Antibiotics kill?
viruses
why can’t Antibiotics kill viruses
They cannot kill viruses as they use body cells to reproduce, meaning any drugs that target
them would affect body tissue too.
define painkiller
relives pain and relives symptoms of infections
example of painkiller
aspirin
define antiviral drugs
treat viral infection
bacteria become more resistant to antibiotics
- bacteria can mutate
-this means they became more resistant to antibiotics
-antibiotics kill the less resistant bacteria
-The resistant bacterias survive and reproduce, meaning the population of resistant bacteria
increases
to prevent bacteria from becoming resistant to antibiotics …
patients must complete the course because the more resistant bacteria live longer and if it is uncompleted the resistant bacteria reproduce
doctors avoid overprescribing antiobotics
aspirin
Aspirin is used as a painkiller (originates from willow)
Digitalis
is used to treat heart problems (originates from foxgloves)
how did alexander fleming discover penicillin?
- alexander fleming discovered this accidentally
- he found mould on his culture plates with clear rings around the mould indicating there were no longer bacteria there
- he found the mould producing the pencilling which killed bacteria
describe the drug testing
preclinical testing ; tested on cells, tissues and then live animals. tested to see how toxic the drug is
Clinical testing: It is first tested on healthy volunteers with a low dose to ensure there are no harmful side effects
clinal trail : tested on unhealthy people or people suffering from the illness The drugs are then tested on patients to find the most effective dose
placebo
is an injection or tablet with no active drug usually made for sugar pill , however some patients will get better from placebo because they think they are getting treated
single-blind
(only the doctor knows whether the patient is receiving
the drug)
double-blind
(neither the patient or doctor knows whether they are
receiving the drug, removing any biases the doctor may have when they are
recording the results).
