The blood cell's JOURNEY OF LIFE

Legend: Deoxygenated, Oxygenated

The blood cells flow through the common carotid artery, to the brain. There, the oxygen is drawn out of the blood. The now deoxygenated blood flows down through the jugular veins, then into the superior vena cava, and into the heart. There, it flows into the right atrium, and is pumped through the AV (atrioventricular) tricuspid valve, and into the right ventricle. Next, it is pumped through the pulmonary semilunar valve, and into the pulmonary trunk. The deoxygenated blood goes through the pulmonary arteries, and into the lungs. Gas exchange occurs, and the blood becomes oxygenated. It goes into the heart through the pulmonary veins, and into the left atrium. It goes through the AV bicuspid valve, into the left ventricle, through the aortic semilunar valve, then finally into the aorta, to the body. 

Pulmonary vs. Systemic

- transports deoxygenated blood to the heart, then the oxygenated blood back to the heart
- pulmonary arteries and veins

- Heart pumping blood to the rest of the body through the aorta
- Superior/Inferior Vena Cava


Arteries and Veins

- thick walls
- carry oxygenated blood
- blood away from heart

- thin walls
- valve to prevent blood flowing backwards
- carry deoxygenated blood
- blood towards to heart

Fetal Circulation

There are 3 major modifications to the fetal circulatory system-

Formenovale  - A hole in the fetus' heart which allows blood to bypass the lungs

Ductus Venosus - Oxygenated blood from the placenta goes through the Ductus Venosus, then to the inferior vena cava

Ductus Arteriosis - A hole between the aorta and pulmonary trunk for blood to bypass the lungs.