Staying healthy Flashcards
What causes malaria?
- Malaria is caused by a protozoan called plasmodium, which feeds on human red blood cells.
What carries malaria?
Plasmodium is carried by mosquitoes, which are vectors (i.e. not effected by the disease) and transmitted to humans by mosquito bites.
What is plasmodium?
Plasmodium is a parasite and humans are it’s host. A parasite is an organism that feeds on another living organism, causing it harm.
What has helped to stop the spread of malaria?
- Knowledge of the mosquito’s life cycle has helped to stop the spread of malaria
- By draining stagnant water
- Putting oil on the water surface and spraying insecticide).
- This knowledge has also helped to develop new treatments for malaria.
Changes in lifestyle and diet can reduce the risk of some cancer:
- Not smoking reduces the risk of lung cancer.
- Using sunscreen reduces the risk of skin cancer.
Difference between a benign tumours and cancer.
- Benign tumor cells, such as in warts divides slowly and are harmless.
- Cancers are malignant tumor: the cells display uncontrolled growth and may spread
What do pathogens do?
- Pathogens (disease-causing organisms) produce the symptoms of an infectious disease by damaging the body’s cells or producing poisonous waste products called toxins.
- Each pathogen has its own antigens, so a specific antibody is needed for each pathogen.
How does the body protect against pathogens?
- The body protect itself by producing antibodies, which lock onto antigens on the surface of the pathogens such as bacteria. This kills the pathogens.
Active and passive immunity
- Human white blood cells produce antibodies, resulting in active immunity. This can be a slow process but has a long-lasting effect.
- Vaccinations using antibodies from another human or animal result in passive immunity which is a quick but short-term effect.
The process of immunisation is also called vaccination:
- It starts with injecting a harmless pathogen carrying antigens.
- The antigens trigger a response by the white blood cells producing the correct antibodies.
- Memory cells (a type of T-lymphocytes) remain in the body, provided a long-lasting immunity to that disease
- Immunisation carries a small risk to the individual, but it avoids the potentially lethal effects of the pathgen,as well as decreasing the risk of spreading the disease.
Difference between antibiotics and antivirals.
- Antibiotics work against bacteria and fungi and destroy a pathogen
- Antivirals work against viruses and an antiviral drug slows down the pathogen’s development.
How are new treatments tested?
New treatments, such as vaccinations, are tested using animals, human tissue and computer models before human trials. some people object to causing suffering in animals in such test.
What is a placebo?
A placebo is a harmless pill. Placebos are used as a comparison in drug testing so the effect of a new drug can be assessed.
What happens in a blind trial?
In a blind trial, the patient does not know whether they are receiving a new drug or a placebo. In a double-blind trial, neither the patient nor the doctor know which treatment is being used. These types of trials avoid a ‘feel good factor’ and a biased opinion.
What happens if antibiotics are used too much?
Excessive use of antibiotics has resulted in resistant forms of bacteria being more common than non-resistant forms. For example. resistant MRSA has thrived, causing serious illness.
