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What is the Digestive System?

In the stomach, the real work of digestion begins. The walls of the stomach secrete a digestive juice called gastric acid, which breaks down chewed-up food particles at the molecular level. Gastric acid is particularly good at breaking down proteins. The muscles of the stomach mix the food particles and the gastric acid together into a semi-liquid mash called chyme. Chyme is stored by the lower stomach and released a little bit at a time through another sphincter—the pyloric sphincter—into the next part of the GI tract: the small intestine.

Chewing and swallowing is just the first step in a complex process through which your body gathers nutrients out of what you eat.

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