Question

How can we count heartbeat without using an instrument?

• A. Exchange of water between body and air.
• B. Absorption of Nutrients from food
• C. Exchange of oxygen and carbon dioxide between air and the body
• D. None of the above

Answer 1

The correct option is C

Exchange of oxygen and carbon dioxide between air and the body

The arteries have muscular walls that expand every time blood is forced into the aorta due to the contraction of the left ventricle of the heart. This can be felt as throbbing in some of the arteries below the skin and is called a pulse. This pulse can be easily felt and counted by pressing your finger gently over an artery on the wrist below the thumb.