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3.2. Digestive system

Digestive system

The digestive system is made up of:

  • The digestive tube, which is about 9 meters long and has a variable shape, widens in some sections and narrows in others. It begins in the mouth and ends in the anus. It has these parts:
    • Oral cavity. The mouth contains the tongue and teeth, and the salivary glands pour saliva into it.
    • Pharynx. It is the common conduit of the digestive and respiratory systems. It communicates the mouth with the esophagus .
    • Gullet. Tube through which food travels from the pharynx to the stomach.
    • Stomach. Widening of the digestive tract, between the esophagus and the intestine, in whose walls there are glands that secrete gastric juices that intervene in digestion.
    • Small intestine. Tube about 6-7 meters long and folded that connects the stomach with the large intestine. It has three parts: duodenum, jejunum, and ileum.
    • Large intestine. It is the last part of the digestive tract, a conduit 1-1.5 meters thick and thicker than the small intestine, made up of the cecum, the colon (ascending, transverse and rectum), and the rectum.
    • AnusOrifice located at the end of the digestive tract. It is made up of a voluntary sphincter muscle that controls the expulsion of stool.
  • The attached glands are organs that discharge their secretions to the digestive tract. They are :
    • The salivary glands: they produce the saliva that they secrete in the mouth.
    • The gastric glands: they produce the gastric juices of the stomach.
    • The intestinal glands: secrete intestinal juices.
    • The liverIt is the largest organ in the body, weighs 1500 grams. It produces bile, which accumulates in the gallbladder, necessary for the digestion of fats.
    • The pancreasGland that secretes hormones into the blood to control the level of glucose in the blood and pancreatic juice that discharges into the duodenum.

Digestive processes

The processes that occur in the digestive system are:

Parts of the digestive tract

Order the parts of the digestive tract:

  • Mouth
  • Pharynx
  • Esophagus
  • Stomach
  • Small intestine
  • Large intestine
  • Anus



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