The Wonderful Structure of Blood Vessels that Deliver Blood in the Body

The heart continuously beats to pump blood throughout the body. Impure blood from the body returns to the heart. There is a well-organized system of blood vessels to keep the blood circulating in the body. Arteries carry blood out of the heart. Arteries branch out into smaller tubes. The structure and function of these blood vessels are amazing. The beating of the heart gives an impulse to the blood, and the blood moves forward in the vessel. There are microscopic valves in the blood vessels so that the blood only moves forward in one direction. There are valves that allow impure blood to ascend upwards from the legs but prevent it from descending back down.

The vessel that carries pure blood away from the heart is called an artery (dhamni), and the vessel that brings impure blood back toward the heart is called a vein ( shira). The green vessels visible under the skin are veins. Arteries are thick; they branch out into microscopic blood vessels, at the ends of which the exchange of nutrients and oxygen from the blood with the body's cells takes place. The blood then becomes impure and travels back toward the heart through the veins.