B6 Preventing and treating disease- biology paper 1 Flashcards
What are antigens?
Unique proteins on the surface of a pathogen that triggers an immune response.
What do antibodies do?
They cause antigens to stick together so that it’s easier for the phagocytes to engulf the pathogen.
What group of cells are the memory cells part of ?
The white blood cells
What do memory cells do?
White blood cells that remember the antibodies that kill a particular pathogen. If you meet that pathogen again, the memory cells can make the right antibodies to kill the pathogens, and so you become immune to the disease.
What is vaccination?
Vaccination involves exposing an individual to the antigens of a particular pathogen , which then triggers an immune response in the formation of memory cells which make antibodies against it. So if you come across this specific pathogen again, your white blood cells will respond immediately and mass produce more antibodies.
What do lymphocytes do?
They detect foreign antigens and then produce antibodies and anti-toxins.
What do phagocytes do?
They produce enzymes to engulf and destroy bacteria.
What is herd immunity?
The idea that if a large proportion of the population is immune to a disease, the spread of the pathogen in the population is very much reduced and the disease may even disappear.
What happens if the number of people taking vaccines drop ?
If the number of people taking vaccines drop, then the herd immunity is lost and the disease can even re-appear.
Give an example of the number of people taking vaccines dropping.
In the UK in the 1970’s, there was a scare over the safety of the whooping cough vaccine. This led to vaccination rates falling from 80% to 30%. In the following years, thousands of children got whooping cough again and a many died. Eventually , however, the vaccine was soon considered safe and people started taking it again .
What does the World Health Organisation want to happen with the measles vaccine?
For 95% of children to have 2 doses of the measles vaccine to give global herd immunity
How many children currently get vaccinated for the measles?
Current figures show that 85% of children get their fist dose, but only 56% get the second
What is the problem with painkillers such as paracetamol and aspirin?
Although they help relieve headaches and sore throats, they have no effect on the viruses that have entered your body and made you feel ill.
What do antibiotics do?
They work inside the body and kill bacteria. They damage the bacterial cells without harming your own cells.
