Oh, wow, oh, oh, wow, oh, wow, oh, wow.

Oh, wow.

Oh, my. Hello, you're listening to The Science of Everything podcast, episode 137, The Digestive System.

I'm your host, James Fodor.

In this episode, we're going to have a journey through the human digestive system

and talk about how we digest and obtain nutrients from our food.

Obviously, this is going to include a coverage of the major components of the digestive system,

including the mouth, the tongue, the esophagus, the stomach, the small and large intestines,

and the accessory organs, including the liver and the gallbladder.

Recommended pre-listing for this episode is episode 25, tissues, organs, and systems. And without further ado, I think we're just

going to jump straight in and start talking about the digestive system, because there's a lot to

cover. So the digestive system is a very large organ system in terms of the amount of space that it

takes up in the body, and it's probably one of the more familiar ones as well. The digestive system is responsible

for processing and absorbing nutrients from our food and then expelling the waste of the non-degestible

products. The complete human digestive system is made up of the gastrointestinal tract plus various

accessory organs. So the gastrointestinal tract or the GI tract

is a passageway that runs from one end of the body right through to the other.

In fact, technically, the inside space within the gastrointestinal tract

is actually topologically, at least, outside of the body.

The food doesn't actually truly enter the body

until it's absorbed across the epithelial cells that line the gastrointestinal tract, but we'll

talk about that later. The GI tract is made up of the mouth through to the esophagus, through

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