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Speaker 1: Welcome to brain Stuff from how stuff works dot com

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Speaker 1: where smart Happens. Hi, I'm Marshall Brain with today's question,

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Speaker 1: how does your stomach keep from digesting itself? Your stomach,

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Speaker 1: if you want to be technical about it, is a

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Speaker 1: crescent shaped, hollow organ about the size of a large melon.

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Speaker 1: The average adult stomach holds about three courts or three

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Speaker 1: leaders of fluid. Your stomach is made up of a

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Speaker 1: variety of layers, including the sarosa, the outer layer that

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Speaker 1: acts as a covering for the other layers, the two

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Speaker 1: muscle layers, the middle layers that propel food from the

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Speaker 1: stomach into the small intestine, and the mucosa. The inner

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Speaker 1: layer made up of specialized cells, including perietal cells, G cells,

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Speaker 1: and epithelial cells. Perietal cells produce hydrochloric acid, a strong

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Speaker 1: asked that helps to break down food. The acid in

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Speaker 1: your stomach is so concentrated that if you were to

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Speaker 1: place a drop on a piece of wood, it would

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Speaker 1: eat right through it. The G cells produce gastron, a

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Speaker 1: hormone that facilitates the production of hydrochloric acid by the

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Speaker 1: perietal cells. The stomach is protected by the epithelial cells,

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Speaker 1: which produce and secrete a bicarbonate rich solution that coats

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Speaker 1: the mucosa. By Carbonate is an alkaline a base and

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Speaker 1: neutralizes the acid secreted by the perietal cells, producing water

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Speaker 1: in the process. This continuous supply of by carbonate is

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Speaker 1: the main way that your stomach protects itself from autodigestion

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Speaker 1: or the stomach digesting itself, and from the overall acidic environment.

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Speaker 1: In some individuals, due to impairments in blood supply to

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Speaker 1: the stomach or to the overproduction of acid, this defense

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Speaker 1: system does not work as well as it should. These

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Speaker 1: people can get gastric ulcers. There are also specific bacteria

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Speaker 1: called Helicobacter pylori that may cause impairment of the stomach's

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Speaker 1: defenses and can also be responsible for ulcers. For more

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Speaker 1: on this and thousands of other topics, visit how stuff

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Speaker 1: works dot com.