This is an I-Heart podcast.

Guaranteed Human.

Welcome to Brainstuff, a production of IHeart Radio.

Hey, Brainstuff, Lauren Boglebaum here.

You might think of your body sort of like a fabulous estate,

with a lot of different departments and individual workers that keep the

household running. For this metaphor, whether you want to imagine yourself as a medieval castle

or a countryside manor or more of a well-staffed but nonetheless haunted mansion is up to you.

You might say that you've got a kitchen staff in your digestive system because it

prepares nutrients for the whole household to use. Organs like your kidneys are part of the cleaning

staff. Your body also keeps a sharp security staff on hand in the form of your immune system.

There are two sub-departments or branches within the immune system,

the innate and the adaptive. A lot of germs that enter your body get dealt with with a swiftness

by your innate immune system. This is a whole organization of defenses that keep out and kick out

any sort of home invader, the home in this case being you.

Your innate immune system includes your skin and mucus membranes, which are physical barriers,

and some cells and enzymes that scan for, attack, and kill any germs that do make it in,

like in a state's physical walls, and its camera network and security

guards. The innate immune system is fairly automated and can't distinguish between different

types of invaders that well, but it's really effective at stopping them before they make you sick.

Unfortunately for us, some germs have evolved to evade our innate immune system.

When, for whatever reason, a germ survives in your body and keeps multiplying, the security guards of the innate immune system call into action that second branch, your adaptive immune system.

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