What are the 7 steps of the digestive system?
Working of the digestive system.
The digestive system consists of the mouth, pharynx, esophagus, stomach, pancreas, and large and small intestines.
The working of the digestive system begins with the ingestion of food through the mouth. Food in the mouth is mixed with saliva. The saliva begins to dissolve the food and the teeth begin to crush and grind the food.
Food is forced back into the throat in the pharynx by the tongue. The pharynx is pulled upward to meet the epiglottis food. Then moves from the pharynx to the esophagus. Food moves down from the esophagus by peristalsis.
The peristaltic waves reach the esophagus finger and then food enters the stomach. The unique muscular structure of the stomach breaks the food into smaller pieces called chimes. The chime exits through the Pyloric sphincter and then to the duodenum or the smaller intestine.
The major portion of digestion and absorption takes place in the smaller intestine.
The mucosa secretes enzymes and supplements, the digestive enzymes of the pancreas and the liver. This completes the chemical process of digestion. The nutrients are transported by the blood to all the cells of the body.
The undigested food reaches the ileocolonic valve and enters the large intestine or colon.
The colon absorbs water, manufactures vitamins, produces mucus, and forms and expels feces. The large interstate pushes the pieces into the rectum which stimulates the defecation reflex.
