Blood Travelling through the Body
Veins and Arteries throughout the human body
Blood travels all around the body providing muscles and organs with oxygen, removing carbon dioxide from the body, fighting infections and illness and closing off wounds. The red blood cells carry oxygen to the organs and muscles. Once the oxygen has been romoved it is replaced with carbon dioxide. The blood then travels up to the lungs to get rid off carbon dioxide and become re-oxygenated.
The diagram to the left displays how blood runs through out the body. Oxygenated blood is red, meanwhile de-oxygenated blood is blue. Veins and arteries although are rather large branch off and become smaller and smaller (arterioles and venules) so that the blood can reach places that it couldn't in the larger arteries and veins. Theblood moves through the arterioles, then through the capillaries and lastly the venules.
The heart is no different from any other organ. It must have its own source of oxygenated blood. The heart is supplied by its own set of blood vessels (coronary arteries). There are two main coronary arteries with two major branches each. They are connected to the aorta (right after the point wher it leaves the heart). In the diagram below you can see the way both oxygenated and de-oxygenated blood
flows through the heart.
The coronary arteries eventually branch into capillary beds. They course throughout the heart walls and supply the heart muscle with oxygenated blood. The coronary veins return blood from the heart. Instead of emptying into another larger vein, they empty directly into the right atrium.
In the diagram below you can see the way both oxygenated and de-oxygenated blood flows through the heart.