The gastrointestinal tract (GIT) involves a hollow muscular tube start off from the oral cavity, where food put through the mouth, starting through the pharynx, oesophagus, stomach and intestines to the rectum and anus, where food is turned out. There are distinct accessory organs that help the tract by releasing enzymes to chew food into its small pieces. Thus the rest organs have played crucial functions in the digestion. Food is moved along the length of the GIT by peristaltic muscular movement of the muscular walls.
The major purpose of the gastrointestinal tract is to break down food particles into nutrients, which can later be absorbed into the body to provide energy to perform vital activities. Very first food go through the process of ingestion into the mouth to be mechanically processed and moistened. Secondly, digestion happens mainly in the stomach and small intestine where proteins, fats and carbohydrates are chemically switched into their basic building blocks. Bitty molecules are then absorbed across the epithelium of the small intestine and afterwards enter the circulation. The large intestine performs a key role in reabsorbing the excess juice. Finally, undigested material and metabolic waste products are excreted from the body via defecation in the form of faces.
System and Functions of Gastrointestinal system:
Mouth act as grinding machine:
Food begins its start point through the digestive system in the mouth, medically termed as oral cavity. Inside the mouth are many accessory organs that help in the digestion of food, i.e. the tongue, teeth, and salivary glands. Teeth breaks food down into small shapes, which are moistened by saliva (secreting by salivary glands) before the tongue and other muscles propelled the food particles into the pharynx.
- Teeth. The teeth are 32 small which prominent out at the age of 18-22, hard organs pitched along the anterior and lateral edges of the mouth. Each tooth is made of a whitest-like mixture called dentin and coated in a layer of enamel—the hardest substance in the body. Teeth are basically a living organs and compose thin blood vessels and nerves under the dentin in a soft portion refer as the pulp. The teeth are made for cutting and grinding purposes.
- Tongue. The tongue is presented on the inferior portion of the mouth between the posterior and medial to the teeth. It is a smallest organ take a shape of different pairs of muscles sink in a thin, bumpy, skin-like layer. The outer surface of the tongue constitutes many rough papillae for better gripping of food as it is propelled by the tongue’s muscles. The taste buds on the outer-line of the tongue helps in detecting taste molecules in food and also connect to nerves in the tongue to signal complete information to the brain. The tongue also play a crucial role to push food toward the posterior part of the mouth for swallowing into the pharynx.
- Salivary Glands. Surrounding the mouth are 3 fixed sets of salivary glands. The salivary glands are important organs that secreted a watery mixture called saliva. Saliva helps to moisten food particles and begins the digestion of carbohydrates, proteins etc. The body also functions saliva to lubricate food molecules as it passes through the mouth, pharynx, and esophagus.
Pharynx providing a route to esophagus:
The pharynx, also known as throat, is a funnel-shaped tube affixed to the posterior end of the mouth. The pharynx functions for the moving of masses of chewed food from the oral cavity to the esophagus. The pharynx also plays a significant part in the respiratory system, as air flow from the nasal cavity proceed through the pharynx on its way to the larynx and finally to the lungs. Because the pharynx works for two varies functions, it fixes with a flap of tissue refer as the epiglottis that behaves as a switch to route chewed food to the esophagus and air to the larynx.
Esophagus as carrier medium between compartments:
The esophagus is a muscular pipe of about 25cm in size and 2cm in diameter. It runs from the pharynx to the stomach after exceeding by way of a hole in the diaphragm. The firm wall of the oesophagus comprises of inner circular and outer longitudinal layers of bulk muscle that are delivered by the esophageal nerve plexus. This nerve plexus surrounds the inferior part of the oesophagus. The oesophagus works mainly as a carrier medium between compartments.
Stomach a muscular storage tank:
The stomach is a buff sac which is being on the very left side of the abdominal cavity, merely inferior to the diaphragm. In the normal person, the stomach equals the size of their a couple of fists put next to each other. This organ works like a storage tank for nutrients in order that the body has time to assimilate bulky meals properly. The stomach also includes hydrochloric acid and digestive enzymes that keep on the digestion of food particles that got going in the oral cavity.
Small Intestine stretched longest fold tube:
The small intestine is a stretched, bilk tube about 1 inch in diameter and approximately 10 feet long that is portion of the inferior gastrointestinal tract. It is fixed just beneath the inferior to the stomach and absorbs most of the space in the abdominal cavity. The whole small intestine is puzzled such as a hose and the internal surface is fully of bulky ridges and folds. These folds are taken in use to boost the digestion and absorption of nutrients. Then it continuous its journey and till that almost 90% food have been utilized.
Pancreas a short lumpy snake:
The pancreas is considerable gland found just inferior and posterior to the abdominal cavity. It is around 6 inches long and shaped akin to short, lumpy snake with its “head” in touch with the duodenum and its “tail” directing to the very left wall of the abdominal cavity. The pancreas produces digestive enzymes into the small intestine to finish the chemical digestion of nutrients.
Large Intestine functions for rest absorbing:
The large intestine is a stretched, firm tube around 2 ½ inches in total diameter and nearly 5 feet lengthy. It is found just inferior to the stomach and also wraps around the high and lateral border of the small intestine. The large intestine help in absorbing water and consists of many symbiotic bacterium that assist in the breaking up of metabolic wastes to get insufficient amounts of energy. Feces in the large intestine leave the body via the anal canal.
- Mouth act as grinding machine.
- Pharynx providing a route to esophagus.
- Esophagus as carrier medium between compartments.
- Stomach a muscular storage tank.
- Small Intestine stretched longest fold tube.
- Pancreas a short lumpy snake.
- Large Intestine functions for rest absorbing.