Vaccination
Biology: Edexcel IGCSE, topic 3.3.16
Vaccination
Vaccination is the main technique for helping the immune system recognise and destroy pathogens. Immunising (making immune) a large proportion of the population will make it very hard for a pathogen to be spread. The process of vaccination is:
Inject a dead pathogen
- A vaccination injects a dead or inactive form of a pathogen into the blood.
Immune system recognition
- White blood cells recognise that the antigens are foreign and produce antibodies against them.
Memory cells
- Some of these white blood cells called memory lymphocytes remain in the blood as memory cells. If the same pathogen invades the body again, the memory lymphocytes can:
- Produce antibodies faster.
- Produce more antibodies. This means that the antibody concentration remains in the blood for longer.
Immunity
- Next time the same pathogen infects the vaccinated person, the immune system will destroy it before it can cause illness.
Test yourself on Vaccination
Which of the following are proven characteristics of vaccination?
Vaccination