Get full information of human digestive system
The human digestive system is made up of their digestive tract and accessory glands. These include the mouth, esophagus, stomach, small intestine, large intestine, and accessory glands such as the red gland, liver, and pancreas.
The mouth is the main organ for food intake. Digestion begins as soon as food is put in the mouth.
The mouth contains teeth, tongue, and salivary glands. Teeth divide food into smaller pieces. The salivary glands produce saliva.
The tongue mixes food with saliva. Saliva is a watery liquid that makes food wet. Wet food can be easily swallowed.
The salivary glands produce an enzyme called amylase, which digests the starch in food and converts it into maltose.
Thus the digestion of food in the mouth remains incomplete as the food stays in the mouth for a short time.
Now half-digested food comes from the mouth into the esophagus. Food is now digested in the stomach from the esophagus.
The stomach is located on the left side of the abdomen. The food stays in the stomach for up to three hours.
The stomach breaks down into small pieces of food and turns them into a semi-solid liquid.
The gastric wall consists of three tubular glands that produce gastric juice. Gastric juice contains dilute hydrochloric acid, pepsinogen enzyme and mucus.
The mucus protects the gastric wall from mild hydrochloric acid, and the pepsinogen enzyme.
Hydrochloric acid supplies the acidic medium to the stomach. It destroys the bacteria that enter the stomach with food.
Enzymes in acidic medium Pepsin incompletely digest the protein in food and convert it into small molecules. Thus the digestion of protein begins in the stomach.
Half-digested food now comes from the stomach into the small intestine.
The ring muscle controls the passage of food through the stomach. The small intestine is the largest part of the digestive system.
In adults, it is about 6.5 meters long. But, the length of the small intestine varies from animal to animal.
It depends on what kind of food the animal eats. Herbivores especially eat grass, so the length of their intestines is long.
Due to the large length of the small intestine, the cellulose present in the grass is easily digested.
Meat is easily digested, so the length of the intestine of non-vegetarians is less.
Carbohydrates, proteins and fats are completely digested in the human small intestine. The small intestine absorbs secretions from the liver and pancreas.
Liver secretes Peters which is a greenish-yellow liquid. It usually accumulates in the gallbladder. Bile is a type of alkaline which is made up of salts.
Bile converts acidic food from the stomach into alkaline. Thus pancreatic enzymes can act on it.
Gallstones break down the fat in food and break it down into small balls. So that enzymes can work and digest easily.
The pancreas secretes saliva. It contains enzymes like amylase, trypsin and lipase. Amylase is made from starch, trypsin from protein and lipase from fat.
The glands in the wall of the small intestine secrete intestinal fluid. The various enzymes of the intestine fully digest carbohydrates into glucose, proteins into amino acids, and fats into fatty acids and glycerol.
The small intestine is the main place for the absorption of digested food after digestion is complete. The small intestine has millions of small courtyard-like structures called rasakunro.
The presence of rasakunro increases the surface area of the small intestine. This helps in faster absorption of digested food.
Digested food absorbed through the small intestinal wall enters the bloodstream.
The blood carries digested food to all parts of the body, and it mixes with the cells. This mixed food is used by all cells in gaining energy, growth, and repair.
Undigested food passes from the small intestine to the large intestine. The large intestine absorbs water from indigestible foods.
Undigested food is now largely converted into solid form. This is excreted through feces.
Waste material is excreted in the form of feces or diarrhea. Waste material is controlled by the mucous membrane of the feces.