Heart and Blood Blood cells carry nourishment to all parts of our body through a network of arteries and veins and an average adult body contains about 4.5 litres of blood. Blood is red in colour and is made up of three types of cells i.e. Red cells, White cells and Platelets and a watery liquid called Plasma. These cells are so small that. a drop of blood may contain millions...

The Urinary System Waste products from the body are regularly let out both in liquid and solid form. The system in the body which is responsible for the production of liquid waste or urine is called the Urinary system. The prime organs in this system are called the Kidneys. All animals with a backbone arid man have two kidneys. Kidneys look like large sized brown beans. Blood which flows from the...

Minerals and Vitamins Chemicals which help our body to stay healthy are called vitamins. These are of six types i.e. Vitamins A, B, C, D, E and K. Vitamin B can further be broken down into a number of types. Vitamins are present in our body but in very small quantities and they need to be supplemented frequently. Different types of foods contain different types of vitamins which is why a...

The Digestive System As we bite into something we want to eat and begin to chew, we initiate the activity of our digestive system. As our teeth crush the food, a watery substance called ‘Saliva’, from our salivary glands, gets mixed into the food to help us in swallowing it. Once we swallow the food, it travels down into our stomach through a tube called the Oesophagus. The oesophagus is located...

Sleep and Exercise Our body needs regular periods of rest. This rest is provided by sleeping, generally at night, and we spend about one third of our life in this activity. When we sleep our muscles are relaxed but our brain continues to work so that it can control our body functions which include breathing, heartbeat etc. A new born child sleeps practically the whole day and wakes up only to...

What is Skin and Sweating Skin is an elastic and waterproof outer layer covering of our body, it protects our body from bacteria and is sensitive to heat, cold and pain. Skin is wear resistant since it constantly renews itself by replacing the upper layer with fresh cells from below. Yet the thickness of the skin can vary from place to place on our body, it may be thin on our...

The Respiratory System Life thrived on Earth primarily because of presence of Oxygen in the air. All animals and creatures living on earth have respiratory systems of various kinds, some may have lungs, others like fish may use gills, and yet others like some insects may breathe through pores in their bodies. Like other creatures and living organisms, man too needs oxygen to survive. When we breathe, air is taken in...

What is Sensation and Reflexes Coming out of the base of the brain is a cluster of nerves which spread all over the body forming the nervous system. The brain stern leads into the spinal cord which extends along the vertebrae upto the tail bone. From the central nerve stem peripheral nerves are extended to the other parts all across the body. These nerves carry messages back and forth from the...