Our heart is an amazing organ that keeps blood moving through the blood vessels in our skin. It pumps blood to the lungs, back to the heart, out to every part of our body, and back to the heart again. The blood makes each round trip in about a minute.
The blood carries digested food and oxygen to all parts of our body. The body needs food and oxygen to stay alive and to grow.
The blood also picks up a waste gas called carbon dioxide. Our blood carries this waste gas from each part of the body back to the lungs. When we breathe out, we get rid of the carbon dioxide gas.
When we relax, our heart pumps about two and a half litres of blood a minute through our body. But if we run or jump, our heart speeds up because our muscles need the extra oxygen for energy. It may pump as much as seven and a half litres of blood a minute.
In boys’ and girls’ age, the heart beats about 90 times a minute. A grown-up’s heart beats about 70-80 times a minute.
To feel your pulse, touch your left wrist below the thumb. Use two fingers from your right hand to do this. Press down gently. The movement you feel is your pulse. You can feel how fast the heart is beating by feeling your pulse.