Stomach
We eat daily but do not know this food changes in alimentary canal. However, we know whatever happens to the food in the mouth. The digestion of the food begins in the mouth. The digestion of the food begins in the mouth. Food is first chewed and crushed under the teeth. The saliva secreted by the salivary glands convents the stomach of food into sugar. Afterwards, the food is swallowed and moved down to the man the stomach by the food- pipe.
The stomach is the widest part of the alimentary canal. It squeeze, twists and churns the contents of food. The action of the stomach turns the food into a semi-liquid state. The small food particles mix up thoroughly with the digestive juice.
The inner lining of the stomach has millions of tiny glands. The gastric juices are secreted by these glands. These juices contain digestive enzymes and acid. The acid also kills many bacteria that enter into stomach along with food. Food remains in the stomach for 2 to 4 hours.
The small intestine is the most vital part of the digestive organs. It is a long tube about 6.5 meters long and 2.5 cm wide. It is the longest part of the alimentary canal. It is coiled but can move freely in the abdominal cavity. The complete digestion of proteins, carbohydrates and fats takes place in small intestine. After the food is digested, it is digested contests are absorbed by the walls of small intestine. Water and other indigestible matters are not absorbed by the small intestine, head towards large intestine.
The small intestine opens into the large intestine which is also called colon. The undigested matters and water pass through the large intestine. There is no digestive function in the large intestine. The walls of the large intestine absorb much of the new of the water. The last segment of the large intestine is called the rectum. It opens to the outside through the anus. The waste matter is thrown out through the anus.