Topic 3 (Infection and Response) Flashcards
What are pathogens
Microorganisms that enter the body to cause disease
What is bacteria
Bacteria are very small living cells that make you feel I’ll by producing toxins that damage your cells
What are viruses
Viruses are extremely small about 1/100th the size of a bacterium. They make you feel I’ll by reproducing in your cells causing them to burst.
What are protists
Protists are single cell eukaryotes. They live in or on other organisms and can cause them damage
What is fungi
Fungi are made ip of hyphae (Thread like structures) which can grow on human skin and the surface of plants causing diseases
What are three ways pathogens can be spread
•Air
•Water
•Direct contact
What is measles
Measles is a viral disease spread by droplets. It cause a red skin rash. It can be very serious and in some cases lead to pneumonia or inflammation of the brain
What is HIV
HIV is a viral seaward spread by sexual contact or exchanging of bodily fluids. It initially has flu like symptoms. The virus attacks the immune system, if the immune system is badly damage it can’t cope with other infections or cancer. This is known as late stage HIV or AIDS
What is tobacco mosaic virus
TMV is a viral disease that affects many species of plants. It causes a mosaic pattern on the leaves of plants. The discolouration means the plant can’t carry out photosynthesis
What is rose black spot
Rose black spot is a fungal disease, it cause black or purple spots to develop on the leaves of rose plants. The leaves turn yellow and drop off, this means less photosynthesis and the plant can’t grow very well
What is malaria
Malaria is a disease caused by a protist. The mosquitoes are vectors, they pick up the malarial protist when they feed on an infected animal, every time it feeds another animal it infects it. Malaria causes repeating episodes of fever which can be fatal.
What is salmonella
Salmonella is a type of bacteria that causes food poisoning, infected people can suffer from fever, stomach cramps, vomiting and diarrhoea. These symptoms caused by the toxins that the bacteria releases
What is gonorrhoea
Gonorrhoea is a STD passed on by sexual contact. It is caused by bacteria. An infected person will get pain when they urinate. Another symptom is thick yellow or green discharge.
How can you prevent diseases
•Being Hygienic
•Destroying Vectors
•Isolating infected individuals
•Vaccination
How does your immune system attack pathogens
•Phagocytosis
•Producing Antibodies
•Producing antitoxins
How does vaccination work
•When you’re infected with a new pathogen, it takes your WBC’s a while to start producing antibodies but by that time you already feel pretty ill
•Vaccinations involve injecting a small amount of dead or inactive pathogens. These carry foreign antigens which causes your body to produce antibodies to destroy them even though they are harmless
•However if the live pathogen of the same type ever appears the WBC’s can rapidly mass produce antibodies as they already dealt with the pathogen before
Positives of vaccination
•Help control a lot of of communicable diseases e.g whooping cough and rubella
•Big outbreaks of disease can be prevented if a large percentage of people are vaccinated (Herd Immunity)
Negatives of vaccination
•Don’t always give you immunity
•Sometimes vaccines give bad reactions e.g swelling
What do painkillers do
They only relieve the pain you are feeling, they don’t actually tackle the cause of the disease or kill pathogens
What do antibiotics do
Antibiotic kill or prevent the growth of bacteria without killing your own body cells. However antibiotics don’t kill viruses as there is no way for them to do so without harming your body cells
How can bacteria become resistant against antibiotics
•When on an antibiotic course, patients may feel better days before the course is up however not all the bacteria may be dead
•If a patient stops taking antibiotics early, bacteria remaining becomes resistant to them. The resistant bacteria reproduce creating more and more resistant bacteria which then causes the patient to feel Ill again.
•The problem is this time the antibiotics will not work as the whole population of bacteria is resistant
•This is why doctors have to be very careful when prescribing antibiotics
Willow Bark makes
Aspirin
Foxgloves make
Digitalis, medicine used to treat heart conditions
Bread mould makes
Penicillin
