Topic outline

    • Internal Organs

      Let’s think of any machine. Think, how does it work? We see many gadgets and machine around us such as washing machine, car, oven, cycle, television, mobile and many more. All these machines are made up of many parts and each has its own function to perform.  Similarly our body functions with help of many parts. Some parts are external which is outside our body such as hands, legs etc. and some are internal parts which inside of the body such as liver, stomach, brain etc.

      Each body part is very important and has special task to do. Some of the internal organs are brain, liver, stomach, heart, lungs, kidneys, small intestine and large intestine.



      Our brain is very delicate and is protected by skull from outside. Brain controls the entire function of our body. Brain receives signals from our sense organs and sends information to other part of the body. It store information and helps to think and learn new things. It control functions such as breathing, digestion, muscles control, emotions, heartbeat etc.



      Stomach is internal organ where most of the digestion takes place. It is a muscular, elastic, pear shaped bag under the ribs. From upper end, it connects to food pipe (esophagus) and lower part leads into the small intestine. Stomach secretes gastric juices which help in the digestion of food.




      Heart is an important organ of our body. It works day and night. We can feel our heart beats on placing our hand on the left side of our chest. Our heart beats about 72 times in a minute. Its job is to circulate blood throughout our body through blood vessels (arteries and veins).

      Heart is a red brown colored muscular organ. It receives de oxygenated blood (impure blood) from different parts of body through veins and pump oxygenated blood (pure blood) to the body through arteries. Arteries appear red in color and carries pure blood that contains nutrients from digested food and oxygen. Veins appear blue in color and carries waste material and carbon dioxide.

      Heart is located in slanting position in the center of chest. The heart has four chambers right atrium, left atrium, right ventricle, and left ventricle.



      Liver lies on the right side of the stomach. It is the largest gland in the body. It secretes and sends bile juice to stomach which helps in digestion. Liver breaks down fats, filters toxins (harmful substances) and controls blood sugar.




      The air we inhale travel through trachea (windpipe) goes to lungs. Lungs are pair of spongy, cone shaped structures located in chest and are protected by rib cage.

      The tiny hairs present in the nose filters particulate matter from the air. Oxygen from air inhaled is absorbed in blood stream and carbon dioxide from the blood stream is expelled and finally we breathe out carbon dioxide through our nose. This process is called gas exchange and takes place in the lungs. Then veins carry oxygen rich blood to the heart and heart pumps to the other parts of the body.

      While breathing in air (called inhalation), our lungs expands and while breathing out air (called exhalation), lungs contracts.



      Kidneys are two bean shaped organs in our body. The kidneys are located at both sides of our backbone just under the rib cage .People are born with two kidneys but we can live healthy life even with one kidney.

      Entire blood in the body passes through kidney many times a day. Kidneys filter water and salts from our blood. The waste get collected in the urinary bladder and thrown out of body as urine.


      Small Intestine


      The small intestine is a long tube. It is 20 feet long and about an inch in diameter. Most of the nutrients are absorbed into our blood stream in small intestine from food we eat and drink. Then food moves from our small intestine to our large intestine.


      Large Intestine

      The large intestine is about 5 feet long and about 3 inches in diameter. The large intestine absorbs water from wastes, creates stool. And then stool enters the rectum and thrown out of the body.


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