The human circulatory system consist of the heart and blood vessels. By the pumping action of heart pure blood is transported from heart to the body parts and impure blood is collected from different body parts towards the lungs. The blood vessel that carry blood from heart to lungs is an exception to carry impure blood. Similarly, the blood vessel that carry blood from lungs to heart is also an exception to carry pure blood. Pumping action of heart is due to contraction and relaxation of the heart and its one complete cycle is called heart beat. The blood vessels that carry impure blood are _______ .

Harshit Singh , 4 Years ago

Grade 12th pass