Overview of Digestive System

The digestive system is an important topic for one-day exams like SSC , Bank PO and other one-day government exams, In this article, we are covering the segment of the digestive system.

The digestive system is the procedure in the human body by which the body responds to the intake of food to provide absorbable nutrients and remove waste products. The digestive system consists of a set of organs that work for each other and transform food into energy for the body.

Morphologically,  the digestive system is made up of the gastrointestinal tract, along with accessory organs such as the liver, pancreas and gallbladder. The mouth, stomach, oesophagus, small intestine, and large intestine, which contains the rectum and anus, are among the hollow organs that make up the gastrointestinal tract (GI tract).

The nutrients in the food we eat have to go through a lot of processing before they can be used to generate energy. This process is known as digestion. The digestive process takes part in the alimentary canal along with other supporting organs and organ systems. In humans, the process is fairly simple due to our monogastric nature, meaning humans have a single-chambered stomach and other animals, such as cows, have four chambers

The process of digestion is also highly altered by some elements of the neurological and circulatory systems.

Part of the Human Digestive System

The digestive system consists of a set of organs that work for each other and transform food into energy for the body. The main organ of the digestive system

Mouth

Food is swallowed through the mouth or oral cavity. The oral cavity or mouth contains the tongue, teeth, and salivary glands. Teeth are designed to grind food particles into smaller pieces and moisten with saliva before the tongue is pushed into the food. pharynx
For example:- Digestion of carbohydrates or starch starts in the mouth itself.

Pharynx

A fibromuscular y-shaped tube combined with the terminal end of the mouth. It primarily participates in the passage of chewed/crushed food from the mouth by the oesophagus. It also has a major part in the respiratory system, as air moves by the pharynx from the nasal cavity on its way to the lungs.

Oesophagus

This is a muscular tube that connects the pharynx, which is a part of the upper section of the gastrointestinal tract. The slightly digested food is pushed inside the stomach by the oesophagus with the help of peristaltic movement. Food cannot enter the windpipe because of the epiglottis. The flap that covers the windpipe is very tiny.

Stomach

The stomach serves as a muscular bag that is placed towards the left side of the abdominal cavity, beneath the diaphragm. Stomach store food and break down the food into small fragments and form a semi-solid paste. Glands that are present in the walls of the stomach secrete gastric juice  This vital organ acts as a storage for the food and provides enough time to digest meals. The stomach also produces digestive enzymes and hydrochloric acid, pepsin, and mucus. that arranged the process of digestion.

• The mucous membranes secrete an aqueous substance known as mucus. It works by covering the gastric pits and stomach lining from the acid that the glands secrete in order to kill the germs that entered with the food particles.
• Digestive enzymes: Digestion of protein begins in the stomach with the help of the pepsin enzyme that works by breaking down polymeric macromolecules such as biopolymers into smaller and simpler substances.
• Hydrochloric acid aids in the breakdown, digestion, and absorption of nutrients like protein.
  Your body is shielded from illness through the removal of viruses and bacteria in the stomach. It works by eradicating dangerous germs found in food particles.

Small Intestine

The small intestine is a thin, long tube about 1 inch in diameter and approximately 10 to 20 feet long.and a part of the lower gastrointestinal tract. The small intestine is placed just behind the stomach and acquires a maximum area of the abdominal cavity. The inner surface of the small intestine is covered in folds and ridges and is completely coiled. The human body’s small intestine is where meals including carbohydrates, proteins, and lipids are completely digested. 

Large Intestine

The large intestine is a long, thick tube with an approximate diameter of 2.5 inches and a length of 5 feet. A portion of the food that our bodies cannot digest or that the small intestine cannot absorb enters the large intestine. Most of the water in the food is absorbed by the intestine’s wall, which solidifies it. The last section of the large intestine, the rectum, is where this solid food is held for a while before being expelled from the body through the anus as faeces or stool. Although the small intestine’s length is longer than the big intestine’s, the latter’s width is larger.

Pancreas

The pancreas is a large gland placed just behind the stomach. It is short with its anterior attached to the duodenum and posterior pointing towards the left part of the abdominal cavity. Another is known for blood sugar regulatory function with the production of insulin. Digestive enzymes aid in the breakdown of lipids, proteins, and carbohydrates and are secreted by the pancreas and released into the small intestine.

Liver

The liver is a roughly triangular, reddish-brown accessory organ of the digestive system placed on the right side of the stomach. Bile juice, which is secreted by the liver and aids in the digestion of fat, is produced by the liver. Normal human liver weight and width are 1.44-1.66 kg (3.2-3.7 lb) and 15 cm, respectively. The liver is the largest gland and the heaviest internal organ in the human body. Other metabolic functions it performs include controlling glycogen storage, breaking down RBCs, and producing the hormone.

Digestion Process

The large intestine’s primary role is to absorb water from undigested food and promote bacterial fermentation of substances that can no longer be digested. Digestion starts in the mouth and concludes in the small intestine.

The gastrointestinal tract, also known as the alimentary canal, is made up of a number of hollow organs and tubes that extend from the mouth cavity into the pharynx, the stomach, the small and large intestines, and finally, finish at the anus. As food particles move through the gastrointestinal tract’s distinct sections, digestion gradually takes place.

The digestion system procedure is complete in the following steps.

Ingestion
The digestion process is the first step (chewing). Before the food is pushed down into the food pipe, salivary glands and the tongue help to lubricate and moisten it.

Mixing and Movement
It participates in the process of lubricating and manipulating food and pushing the food by the food pipe (using peristalsis), and into the inside of the stomach.

Secretion
The stomach, small intestine, liver, and pancreas secrete enzymes and acids to help in the process of digestion. Its main role is to break down food particles into small components and easily absorbable components.

Digestion
The process of transforming complex food particles into simpler elements in the presence of enzymes and acids produced by different digestive organs.

Absorption
The small intestine, where the majority of nutrients and minerals are absorbed, is where this process starts. The big intestines take up any extra water present in the indigestible material.

Excretion
the procedure of eliminating waste products and indigestible substances from the body by faeces.

Functions of the Human Digestive System

• The digestive system’s two primary activities are digestion and absorption.
• The body needs digestion to convert food particles into nutrients for energy production, cell development, and repair.
• For nutrients from food and liquids can be absorbed by the circulation and transported to the cells throughout the body, they must first be broken down into smaller molecules.
• The body converts the nutrients found in food and drink into proteins, lipids, carbs, and vitamins.