Answers to AQA GCSE Vaccination (Biology)

Practice Questions

1.State two reasons why we vaccinate individuals

1.Prevent some communicable diseases in individuals

2. Reducing the spread of pathogens by vaccinating a large proportion of the population.

2. Summarise how vaccines work to protect us against communicable disease

Vaccination involves introducing small quantities of dead or inactive forms of a pathogen into the body to stimulate the white blood cells to produce antibodies.

If the same pathogen re-enters the body the white blood cells respond quickly to produce the correct antibodies, preventing infection.

3. Define the term herd immunity

Herd immunity is when enough people in a population are vaccinated or immune so that a disease cannot spread easily.