Every gut microbe has a job to do. Find out who these millions of different microbes are and what their jobs are within the ecosystem that is you, from the wonderful TEDEd: You Are Your Microbes. Full lesson here. From jtotheizzoe:

Sure, you feel human, but that’s only mostly right. In and on your body, you’re outnumbered by ten times when it comes to microbes. And many of them have essential duties that we just couldn’t do by ourselves. Here’s a trip through your microbial inner universe … what we call the “microbiome”.

A lesson by Jessica Green and Karen Guillemin for TEDEducation.

PreviouslyThe family tree of your microbiome, the “kitten microbiome” and more.

And don’t miss this Radiolab episode all about Guts.

In the archives: more about our health, including Flu Attack! How A Virus Invades Your Body and Sugar: Hiding in plain sight.