What Is a Vaccine?
What Is a Vaccine?
A vaccine contains a harmless form of a pathogen or its antigens. This may be a dead or weakened pathogen, fragments of its surface, or genetic instructions for making a harmless antigen.
Step-by-step lessons on AQA GCSE Biology 3.1.7 Vaccination. Each one builds up to exam-style questions. Start with the foundational topics and build up to the higher-tier material.