Infection and response Flashcards
What are pathogens?
They are micro-organisms
They are communicable and plants and animals can also become infected by them.
What is bacteria?
Bacteria are small cells
They reproduce in the body very quickly.
Toxins are produced to make you feel ill and damage your cells and tissues.
what are viruses?
They are smaller than bacteria
They reproduce quickly also.
They replicate as they live inside our cells
Then they burst out of the cells releasing new viruses
What are protists?
They are multicellular
some protists are parasites that live on or inside other organisms
protists are often carried by a vector
What is fungi?
Some are single celled and some have hyphae
The hyphae penetrate and grow onto human skin
This can also occur on the surface of plants
How are pathogens spread?
Water e.g cholera
Air e.g influenza
Direct contact e.g athletes foot
Why have vaccinations been invented?
To protect and prevent us from having diseases
Prevent a pandemic or epidemic
What is vaccination?
The process of injecting a dead or weakened pathogen into the body.
Two vaccine pros
helps control communicable diseases that used to be common
epidemics can be prevented
Two vaccine cons
They don’t always work
people can have a bad reaction to it
salmonella is a bacteria, what are the symptoms?
Fever, stomach cramps , vomiting and Diarrhoea
What does the Uk do to prevent food poisoning?
They vaccinate the vast majority of the poultry in the Uk
How do you prevent the spread of salmonella
Hygiene - washing hand regularly
Destroying Vectors- using insecticides or destroying their habits
isolation- isolating the infected person prevents the spread
vaccination- making sure people can not develop the infection and pass it to other people
Measles is spread through droplets of liquid and coughing and sneezing, what are the symptoms?
Red rash on skin, fever
What does MMR stand for?
Measles, mumps and rubella
why are people vaccinated against measles at a young age?
to prevent pneumonia
What Is the 4 stages of fighting against diseases?
skin stands as a barrier to pathogens
mucus and hair in our nose traps the particles
Trachea and bronchi emit mucus to trap pathogens (they include cilia that move backwards and forwards transporting mucus towards the throat)
pathogens that enter the body through the mouth are killed by the hydrochloric acid of the stomach
What does the immune system do?
It destroys any pathogens that enters the body
What are the 3 main types of WBC and what are their roles
phagocytosis - WBC engulf and digest pathogens
produce antitoxins neutralising the toxins
produce antibodies. pathogens have antigens on their surface and antibodies are invented to lock onto the antigens.
What is pre- clinical testing?
Drugs tested on human cells and tissues
Drugs carried out on live animals
What is clinical testing?
Tests on healthy humans on a low dose, then tested on patients with the illness to find the right dose.
What is placebo?
Substance like the drug but does not cause any harm
what is the placebo effect?
When the patient thinks the treatment will work but nothing happens
what is the blind trial?
patient is unsure as to weather they are receiving the drug or placebo
What is the double blind trial?
When the doctor and patient is unsure as to weather they are getting the drug
what other chemicals can be used to treat diseases?
Drugs from plants
give one example of a fungal disease
Rose black spot
What is malaria caused by?
protists
What are the vectors and how do they become infected?
The vector is mosquitos and they become infected when feeding on an infected animal
how can the protist cause fevers?
by going into the blood vessels
Explain how a population of antibiotic resistant bacteria might develop from the non resistant bacteria.
(3 marks)
idea that bacteria mutate
leading to bacteria resistant cells that survive antibiotics
They then copy and multiply
