The digestive system is a system of body that provides energy for the functions of entire body. Digestion process begins from mouth with chewing. When we chew food in the mouth, saliva is mixed with food and convert carbohydrates in to glucose. After that, food reaches inside the stomach through food pipe (oesophagus) and stays for about 3 hours. Here, different types of digestive juices (enzymes) mix with food and complete digestion process.
After this process, food is converted in to liquid form and forwarded in small intestine. In duodenum the first part of small intestine, digestive juices secreted from pancreas gland and gall bladder mix with food and digestion process starts again. And then, food is reached in the last section of small intestine where nutritive elements of food are absorbed by blood and wastes products are forwarded in to large intestine. From here, these wastes are come out from anus by excretory systems.
The digestive system is a system of body that provides energy for the functions of entire body. Its main works are- intake of food, digestion of food, mixing nutritive elements in the blood and removes out undigested and wastes food through anus.
Food has to pass through three processes inside our body-
Digestion and absorption of food is the works of digestive systems, but metabolism is completed by body cells.
Before knowing the important organs of the digestive systems and their functions, it is necessary to understand the structure of the wall of alimentary canal or gastro intestinal tract or digestion tract.
Digestion is a mechanical and chemical process. In it, the food is broken in simpler forms and after that by the action of different types of enzymes and digestive juices, it is converted in to more simpler form (paste) so that blood could absorb it easily and could be used by cells. The physical and chemical processes through which insoluble food particles are made soluble for assimilation, are called digestion. The process of digestion is done mainly by the actions of digestive juices secreted from digestive organs. In the process of digestion, carbohydrates, glucose, fructose, galactose, sucrose, maltose, lactose, etc. are converted into simple sugars. Proteins, amino acids and fat are converted into fatty acids and glycerol. Carbohydrates, fats and proteins are broken by digestive organs in to such simpler form (fluids) so that could be absorbed by tissues easily. Water, mineral salt and vitamins are being absorbed in the form as eaten and the body cells use them properly. The substance did not able to be digested in the intestines, comes out as faecal materials from the body.
The digestive tube is chiefly present in digestive organs. This digestive tube is also called alimentary canal and digestion is being competed only in it with the help of digestive juices.