What is the function of the GI tract?

What is the function of the GI tract?

The digestive system is composed of the gastrointestinal (GI) tract or the alimentary canal, salivary glands, the liver, and the exocrine pancreas. The principal functions of the gastrointestinal tract are to digest and absorb ingested nutrients and to excrete waste products of digestion.

What are the three major functions of the mucosa?

The mucosa has subdivisions called surface epithelium, lamina propria, and muscular layer. Its major functions include secretion of enzymes, mucus, and hormones, absorption of digested foodstuffs, and protection against bacterial invasion.

What is the special function of the mucosa in the esophagus?

What is the special function of the mucosa (layer 1) in the esophagus that explains why it is relatively thick and smooth while in most areas of the digestive tract the mucosa is relatively thin and folded? To protect the rest of the esophagus from sharp food particles and stomach acid.

What is mucosa in the digestive system?

The mucosa, or mucous membrane layer, is the innermost tunic of the wall. It lines the lumen of the digestive tract. The mucosa consists of epithelium, an underlying loose connective tissue layer called lamina propria, and a thin layer of smooth muscle called the muscularis mucosa.

Why is the GI tract important?

The gastrointestinal tract, the key interface between ingested nutrients and the body, plays a critical role in regulating energy homeostasis. Gut-derived signals convey information regarding incoming nutrients to the brain, initiating changes in eating behavior and energy expenditure, to maintain energy balance.

Where is mucosa found in the body?

Mucous membranes line many tracts and structures of the body, including the mouth, nose, eyelids, trachea (windpipe) and lungs, stomach and intestines, and the ureters, urethra, and urinary bladder.

What is a major function of pancreatic juice?

During digestion, your pancreas makes pancreatic juices called enzymes. These enzymes break down sugars, fats, and starches. Your pancreas also helps your digestive system by making hormones. These are chemical messengers that travel through your blood.

How does the esophagus help the digestive system?

Esophagus: The esophagus is a muscular tube that connects the pharynx (throat) to the stomach. The esophagus contracts as it moves food into the stomach. A “valve” called the lower esophageal sphincter (LES) is located just before the opening to the stomach.

How long is the esophagus in the human digestive system?

The esophagus is about 8 inches long, and is lined by moist pink tissue called mucosa. The esophagus runs behind the windpipe (trachea) and heart, and in front of the spine. Just before entering the stomach, the esophagus passes through the diaphragm.

What are the four layers of the digestive tract?

All segments of the GI tract are divided into four layers: the mucosa (epithelium, lamina propria, and muscular mucosae), the submucosa, the muscularis propria (inner circular muscle layer, intermuscular space, and outer longitudinal muscle layer), and the serosa (Figure 1).

Where does mucus come from in the GI tract?

The mucosa contains specialized goblet cells that secrete sticky mucus throughout the GI tract. On the mucosa layer, small finger-like projections called villi and microvilli help to increase surface area for nutrient absorption.

Which is responsible for movement of food down the GI tract?

Muscularis mucosa of the submucosa: The muscularis mucosa is adjacent to the submucosa, and should not be confused with the muscularis externa. The muscularis externa is responsible for segmental contractions and peristaltic movement in the GI tract. These muscles cause food to move and churn together with digestive enzymes down the GI tract.

Where is the mucosa located in the digestive system?

The mucosa surrounds the lumen, or open space within the digestive tube. This layer comes in direct contact with digested food (chyme). The epithelium of the mucosa is particularly specialized, depending on the portion of the digestive system.

What are the four layers of the gastrointestinal tract?

The gastrointestinal (GI) tract is composed of four layers of tissue, known as tunics. Each layer has different structures and functions. From the inside out they are called the mucosa, submucosa, muscularis externa, and serosa.