The Circulatory System
There are 3 types of blood vessels:
Arteries – this type of blood vessel carries blood away from the heart. This blood is oxygen-rich and takes it to the body’s tissues. They do branch into smaller and smaller as they get farther away from the heart and into the organs.
Capillaries – these are small, thin blood vessels that connect the arteries with the veins. This is where the exchange of oxygen, carbon dioxide and other wastes from our organ cells take place.
Veins – these are the blood vessels that takes the blood back to the heart. These get bigger and bigger the closer you get to the heart. The superior vena cava is the large vein that brings blood from the head and arms to the heart and the inferior vena cave brings blood from the abdomen and legs to the heart.
The arteries, veins, and capillaries is over 60,000 miles long. That is long enough to go around the world more than twice. Pretty impressive.