The center of the circulatory system is the heart, which is the main pumping mechanism. The heart is made of muscle. The heart is shaped something like a cone, with a pointed bottom and a round top. It is hollow so that it can fill up with blood. An adult’s heart is about the size of a large orange and weighs a little less than a pound. Apr 07, · Before we tackle the blood flow through the heart, let’s first review the anatomy and physiology involved. Pulmonary Circulatory System: It is responsible for the circulation of unoxygenated blood from the heart going to the lungs (passing the pulmonary artery). Oxygenation of the blood takes place in the lungs, then returns to the heart (already oxygenated) via the pulmonary vein.
May 14, · Deoxygenated blood enters your heart through the right atria from where the blood moves into the right ventricle first and then to the lungs through the pulmonary artery. Your left atrium receives oxygenated blood from the lungs, which is then pumped into the left ventricle from where it moves into the aorta and then to the different parts of your body. Apr 15, · Blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. As the atrium contracts, blood flows from your right atrium into your right ventricle through the open tricuspid valve. When the ventricle is full, the tricuspid valve shuts.