In the 1st loop of blood to and from the heart, blood enters through the veins, travels through the atrium, goes through the valve, travels through the ventricle, goes through the valve and into the and exits to the body.

In the 1st loop of blood to and from the heart, blood enters through the pulmonary , travels through the left , goes through the bicuspid , travels through the left , goes through the aortic and into the and exits to the body.

In the 2nd loop of blood to and from the heart, the blood enters through the vena cava, passes through the atrium and the valve, then passes through the ventricle and the valve. Finally, it enters the artery and leaves the heart to go to the .

In the 2nd loop of blood to and from the heart, the blood enters through the superior , passes through the right and the tricuspid , then passes through the right and the pulmonary . Finally, it enters the pulmonary and leaves the heart to go to the .