Vaccine - A biological preparation that improves the immune system’s ability to recognize and destroy harmful infectious agents.⏎
Species - One of the most basic units of biological classification, ranking just below the genus and comprising individuals or populations capable of interbreeding.⏎
Suburbanization - The process of land conversion and development around the periphery of major cities.⏎
Virus - An infectious agent that is only capable of replicating itself inside the living cells of other organisms.⏎