Explain the role of the stomach in the digestive process

Answer 1

The stomach is uniquely equipped to carry out two important digestive functions: (1 ) mixing food with the gastric secretions that aid in chemical digestion and (2 ) temporarily storing food. Specialized cells in the lining of the stomach produce a variety of substances that aid in the process of digestion. These digestive secretions, collectively referred to as gastric juice, consist mainly of water, hydrochloric acid, digestive enzymes, mucus, and intrinsic factor, a protein that is essential to vitamin B12absorption.In the stomach, muscular contractions mix food with gastric juice, causing the chemical and physical breakdown of food into chyme. The presence of food in the stomach stimulates the release of a hormone called gastrin, which is produced by special cells in the stomach's lining. Gastrin stimulates the release of gastric juice and causes the muscular wall of the stomach to contract vigorously. These powerful muscular contractions, much like the action of kneading bread, force the bolus to mix with the acidic gastric juice. Within 3 to 5 hours after eating a meal, the partially digested food is mixed thoroughly with the gastric juice. By the time the bolus leaves the stomach, it has been transformed into a semi-liquid paste called chyme.It is important that all the digestive events that are supposed to occur in the stomach do so before chyme enters the small intestine. To make sure that this happens, the stomach serves as a temporary storage facility. As your stomach fills with food, its walls expand. This stretching triggers a neural response, signaling the brain that the stomach is becoming full. In turn, the brain sends a signal that hunger has been satisfied, causing a person to stop eating. Feeling this sensation of fullness is an important aspect of regulating food intake. The pyloric sphincter, located at the base of the stomach, regulates the flow of chyme into the small intestine.