Topic outline

    • Digestive System

      All living things eat food for energy. Food we eat is broken into small pieces for the body to absorb. The nutrients from food are absorbed in the body and used for energy. Our body uses this energy for work, play and growth. The process of breaking down of food into smaller particles that can be absorbed by our bodies is called digestion.


      The organs involved in the process of digestion are mouth, food pipe (esophagus), stomach, small intestine, liver, pancreas, large intestine and anus.

      Mouth – Digestion starts with mouth. Teeth help to chew and grind the food into simpler particles. Salivary gland secretes saliva that helps to soften the food and helps in further breaking down of food.


      Tongue – Tongue is a muscular organ that helps in mixing of saliva with food which makes swallowing of food easy. Tongue contains taste buds such as sweet, sour, salty and bitter.


      Esophagus - Esophagus is a muscular tube from the mouth to the stomach. When we swallow, food goes down the esophagus and reaches our stomach.


      Stomach – The stomach is a sac-like organ with strong muscular walls.It can store food for several hours. In the stomach gastric juices secereted by stomach breakdown the food further into paste. From stomach food moves to small intestine.


      Small intestineThe small intestine is a tube that is about 18 feet long. In the small intestine, food mixes with juice secreted by pancreas (helps in digestion of carbohydrates) and liver (bile juice secreted by liver is stored in gall bladder).Here food is changed into fine particles which can easily absorbed through the walls of small intestine and finally into the blood. Most of the nutrients from the food are absorbed in the small intestine.

      Large intestine – From small intestine undigested food passes to large intestine. It is 5 – 7 feet long. Water is absorbed here. The undigested food passes through the large intestine and sent out from anus.


      Healthy eating habits

            1.   Wash your hand before eating.

            2.   Eat lots of fruits and vegetables.

            3.   Avoid eating oily and junk food.

            4.   Chew slowly for easy digestion.

            5.   Drink 6 – 8 glasses of water.


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