Regulation of the Digestive Process

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The body coordinates the various steps of digestion so that the process proceeds smoothly and cells obtain a steady supply of nutrients and energy. The central nervous system and various glands control activities that regulate the digestive process, such as the secretion of enzymes and fluids. For example, the presence of food in the esophagus, stomach, or intestines triggers peristalsis. Food entering the stomach also stimulates the central nervous system to initiate the release of gastric juice. And as hydrochloric acid passes from the stomach, the small intestine produces secretin, a substance that simulates secretion of pancreatic juice.

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