After chewing and salivation, we form what we call food cake, which is swallowed. After swallowing, the food bolus passes through the pharynx and reaches the esophagus.
The pharynx is an elongated funnel-shaped cavity organ located just beyond the mouth. It communicates with the mouth, nasal cavities, larynx, and esophagus. When food reaches the pharynx, the muscles in your wall contract and push the food into the esophagus.
When food reaches the pharynx, the muscles in your wall contract and push the food into the esophagus. In the region between the mouth and pharynx are the right and left palatine tonsils (tonsils). They are defense organs of the body.
The esophagus is a tube-shaped organ with flexible walls that measures approximately 25 centimeters in length. In its upper wall, it communicates with the pharynx; in its lower part, communicates with the stomach. Through peristaltic movements, the esophagus pushes food into the stomach.
Swallowing is a voluntary movement, that is, we consciously perform the act of swallowing. From there, the peristaltic movements lead the food bolus through the digestive tract. These movements are involuntary, that is, they are independent of our will. These are contractions of the muscles in the esophagus, stomach and intestines, where they are most intense. In addition to pushing the food along the digestive tract, they promote their mixing.
Peristaltic movements participate in the mechanical digestioncausing the food bolus to be pushed from the esophagus to the stomach. A valve, the cardia, regulates this passage of food.
Valve: diminutive, is a mechanical and biological structure that makes it possible to regulate or interrupt the passage of a substance from one location to another. A good example is the sphincter, a valve that regulates the passage of feces through the anus.
In the stomach, the peristaltic movements mix the food bolus with the gastric juice, produced by the mucous glands. This juice contains hydrochloric acid, which maintains stomach acidity, making the enzymes work in the stomach.
THE pepsin, the main enzyme in the stomach, acts on protein transformation by intensifying chemical digestion, which will continue in the gut. The food juice resulting from gastric digestion is called chyme; This is why gastric digestion is also called chemification. Through another valve - the pylorus - the passage of the chyme to the intestine is regulated.