什么是单胃消化?

The human body contains a monogastric digestive system, the presence of one stomach chamber to digest food.

Digestion begins with a cephalic phase, during which the brain sends signals that tell the body to prepare to take in food. Ingestion, the intake of food, occurs in the oral cavity, or mouth.

The teeth begin to mechanically break down large particles of food while saliva from the salivary glands, full of different enzymes like amylase and lipase, starts the process of chemical digestion.

From here, the tongue pushes the bolus into the pharynx, which opens into the esophagus. Via peristalsis, smooth muscle contractions, the food mass moves unidirectionally down the long tube of the esophagus and into the stomach, an acidic environment containing gastric juices, including key enzymes.

The cardiac sphincter at the top of the stomach prevents acidic stomach contents from damaging the esophagus.

As the stomach churns due to contraction and relaxation of smooth muscles, the contents are turned into a mixture, known as chyme, partially digested food and gastric juices. Small amounts of chyme are then released by the pyloric sphincter toward the small intestine. Nutrients can now be absorbed into the blood stream by passing through the highly folded epithelial cell lining, called the villi.

What is left behind, the undigested material, then travels to the large intestine where the absorption of water takes place and the remaining waste material forms feces to be stored in the rectum until excretion.