The Digestive System

1. The Digestive System By: Davyn Leon, Roy Mandanas, and Carl Jimenez The digestive system consists of the mouth, teeth, esophagus, stomach, and intestines.

2. The mouth is a chamber for ingestion and initial processing. • Inside the mouth the tongue mixes food with a mucous solution, saliva. • Saliva moistens and lubricates the food so that it is easier to swallow and does not abrade the tissue of the esophagus as I passes through. The Mouth

3. The esophagus actively moves a processed lump of food called a bolus, through the action of muscles. • In many vertebrates, the movement of food from the esophagus into the stomach is controlled by a ring of circular smooth muscle, or a sphincter, that opens in response to the pressure exerted by the food. Esophagus

4. The Stomach is a “holding station” involved in acidic breakdown of food • The stomach is a saclike portion of the digestive tract. • Its inner surface is highly convoluted, enabling it to fold up when empty and open out like an expanding baloon with food • The Stomach contains a third layer of smooth muscle for churning fod and mixing it with gastrice juice, an acidic secretion of the tubluar gastric glands of the mucosa Stomach

5. The Structure of the small intestine is specialized for digestion and nutrient uptake • Small intestine is approximately 4.5 m long in a living person, but 6 m long at autospy when all the muscles have relaxed. The first 25 cm is the duodenum; the remainder of the small intestines is divided into the jejunum and the ileum. • The main organs that aid digestion are the pancreas, liver, and galbladder. intestines