Check out our Patreon page: https://www.patreon.com/teded View full lesson: https://ed.ted.com/lessons/how-does-the-immune-system-work-emma-bryce The immune system is a vast network of cells,...
========== A mosquito lands on your arm, injects its chemicals into your skin,
and begins to feed. You wouldn’t even know it was there,
if not for the red lump that appears, accompanied by a telltale itch. It’s a nuisance, but that bump
is an important signal that you’re protected
by your immune system, your body’s major safeguard
against infection, illness, and disease. This system is a vast network of cells,
tissues, and organs that coordinate your body’s defenses
against any threats to your health. Without it, you’d be exposed to billions
of bacteria, viruses, and toxins that could make something as minor
as a paper cut or a seasonal cold fatal. The immune system relies on millions
of defensive white blood cells, also known as leukocytes, t...