Our immune systems consist of two parts: the innate (or general) immune system and the adaptive (or acquired) immune system. In this video, I explain the basics of these immune systems, illuminating how they each fight germs (like bacteria, viruses, and fungi) and foreign substances (like chemicals and splinters).

I also define: antigens, antibodies, inflammation, phagocytes, natural killer cells, B cells, and T cells, and I explain the brilliant cascade by which the innate and adaptive immune systems work together to protect us from illness year-round and life-long.

A brief explanation of immunological memory and vaccination is also offered.

Video commissioned by Allergy Research Group and first appeared on their blog. Re-posted here with their gracious permission.