Why is digestion called chemical change

Definition Digestion describes all processes that serve to convert ingested food into chemical substances so that they can be transported to the cells of the body via the blood and partly via the lymphatic system. The removal and excretion of waste products from cell metabolism are also part of digestion.

The digestive process begins in the mouth. Solid food is broken up by chewing and softened by saliva. Saliva contains enzymes that break down carbohydrates into sugar molecules.

The chyme enters the stomach through the esophagus. There the food is processed mechanically and chemically. There are around 3 million glands in the gastric mucosa that produce around 3 liters of gastric juice every day. The gastric juice contains a weak hydrochloric acid and enzymes.

In the duodenum, the chyme is mixed with enzymes from the pancreas and bile acid, among other things. Enzymes and bile ensure that fats can be broken down and optimally absorbed by the mucous membrane of the small intestine. In addition, glands in the mucous membrane of the small intestine secrete digestive juice that breaks down proteins and carbohydrates. This mucous membrane consists of millions of finger-like processes called villi. In these villi, the food components are absorbed by the blood and waste products are released into the intestine for excretion.

The small intestine transports the indigestible components and water into the large intestine by rhythmically contracting the intestinal muscles, the so-called intestinal peristalsis. There the water is absorbed together with minerals and vitamins. The venous, oxygen-poor and nutrient-rich blood from the stomach, intestines and sometimes also from the spleen and pancreas collects in the so-called portal vein and is forwarded to the liver. There, proteins, fats and carbohydrates are further broken down or broken down, get back into the blood and are transported to the body cells. Food residues and degradation products are excreted through the rectum.

The digestive organs are also known as the digestive or gastrointestinal tract, the transport of food as the gastrointestinal passage. Depending on the composition of the food, it takes 24 to 30 hours, sometimes even several days, for the entire digestive process to be completed.

Indigestion can lead to diarrhea, constipation, or gas. Flatulence is caused by a change in the natural colonization of bacteria in the large intestine. Fermentation processes lead to increased intestinal gases that escape uncontrollably or with the stool. Flatulence can also lead to intestinal colic and occur in connection with constipation. Regardless of this, however, there are also flatulent foods such as beans, cabbage or freshly baked bread.