The parts of the human digestive system

Digestive Medically reviewed by Healthline Medical Team on February 4, The human digestive system is the means by which tissues and organs receive nutrients to function.

The parts of the human digestive system

By Editors Digestive System Definition The digestive system is a group of organs consisting of the central gastrointestinal GI tract and its associated accessory organs that break down food into smaller components so that nutrients can be absorbed and assimilated, providing energy and sustaining the body.

Digestive System | Everything You Need to Know, Including Pictures

The GI tract is a long tube of varying diameter beginning at the mouth and ending in the anus. The glands of the digestive system consist of the tongue, salivary glandsliver, gall bladder and pancreas.

Digestion can be divided into three stages — the oral phase mouththe gastric phase stomach and the intestinal phase small intestine — depending on the position of food within the digestive tract.

At each stage, different nutrients are digested, under varying circumstances. The GI tract begins to form early during human development, in the third week after fertilization.

Functions of the Digestive System

Around the 16th day of development, the primitive gut is formed through invaginations of embryonic cells. The initial structures of the digestive system extend from the buccopharyngeal membrane to the cloacal membrane.

The mouth forms when the buccopharyngeal membrane breaks down and opens the tract to amniotic fluid. For the rest of fetal development, amniotic fluid is actively swallowed.

Functions of the Digestive System The organs of the digestive system work together so that complex biomolecules in food are broken down into their simple monomers and absorbed by the body. A number of secretions and the activity of a variety of enzymes, starting from the mouth till the intestines, are involved in this process.

The internal structure of the different glands and organs of this system reflect their particular roles, such as the stomach containing multiple muscle layers in order to churn and mix food, or the mouth having salivary glands and teeth for grinding and lubrication.

Each organ has a distinct pH and a special set of proteins, electrolytes and enzymes to facilitate their activity. Different parts of the digestive system are also regulated together, depending on the progression of food through the GI tract.

Another important function of the digestive system is the removal of undigested food particles through egestion.

The mouth maintains a nearly neutral pH, due to the presence of saliva, though the pH of the mouth can vary temporarily based on the food being ingested.

The stomach has the lowest pH in the digestive system, occasionally reaching as low as 1.

The parts of the human digestive system

Immediately afterwards, though, the enzymes of the small intestine function at a pH between 6. Secretions of the pancreas and liver, consisting of alkaline bile and bicarbonate ions, mediate this remarkable alteration.

The Human Digestive System: Functions, Definition, Organs

The separation of the stomach from the small intestine is also maintained by the pyloric sphincter of the stomach — a small band of smooth muscle that acts like a valve, regulating the movement of chyme from the stomach into the intestine and preventing its regurgitation. The regulation of digestive secretions can be divided into three phases — the cephalic, the gastric and the intestinal phases.

The digestive system is made up of the gastrointestinal tract—also called the GI tract or digestive tract—and the liver, pancreas, and gallbladder. The GI tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus. The digestive system uses 3 main processes to move and mix food: Swallowing. Swallowing is the process of using smooth and skeletal muscles in the mouth, tongue, and pharynx to push food out of the mouth, through the pharynx, and into the esophagus. The functioning of the human body is credited to the collective work of the organ systems, and the digestive system is one of them. It comprises various organs that aid in the digestion of food and assimilation of nutrients.

The initial cephalic phase is the secretion of digestive enzymes and secretions at the sight, smell or thought of food. The gastric phase of regulation begins when food is swallowed. The stomach immediately begins to prepare to receive food through the esophagus.

The intestinal phase is associated with the duodenum and not only influences the release of secretions form the liver and pancreas but also provides feedback to the stomach, altering its secretions and activity through neuronal and hormonal mediators.

Organs of the Digestive System It is useful to consider the organs of the digestive system from a developmental standpoint.

Digestive System Anatomy

Until birth, the primitive gut is divided into three segments — the foregut, midgut and hindgut. The foregut comprises the mouth, salivary glands, esophagus, stomach, liver, gall bladder, the superior portion of the pancreas and the initial sections of the duodenum in the small intestine.parts of the digestive system The digestive system consists mainly of a long muscular tube, the digestive tract.

This starts at the mouth, continues via the oesophagus and stomach to the intestines, and ends at the anus. The functioning of the human body is credited to the collective work of the organ systems, and the digestive system is one of them.

It comprises various organs that aid in the digestion of food and assimilation of nutrients. The digestive tract (or gastrointestinal tract) is a long twisting tube that starts at the mouth and ends at the anus. It is made up of a series of muscles that coordinate the movement of food and.

The digestive system uses 3 main processes to move and mix food: Swallowing. Swallowing is the process of using smooth and skeletal muscles in the mouth, tongue, and pharynx to push food out of the mouth, through the pharynx, and into the esophagus.

The digestive system uses 3 main processes to move and mix food: Swallowing. Swallowing is the process of using smooth and skeletal muscles in the mouth, tongue, and pharynx to push food out of the mouth, through the pharynx, and into the esophagus.

The digestive tract begins this involuntary process once food is consumed.

The parts of the human digestive system

The human digestive system is the means by which tissues and organs receive nutrients to function. The system breaks down food, extracts nutrients from it, and converts them into energy.

Digestive System - Definition, Function, Organs & Diseases | Biology Dictionary