Heart

The heart is responsible for pumping blood continuosly all throughout the life of a pig. It supplies the body with oxygenated blood, hormones and other necessary substances. It also carries away metabolic waste products from the cells of the body such as carbon dioxide which it transports to the lungs where it can be exchanged for oxygen.

The pig (similarly to human) heart has 4 chambers; Two upper ones called Atria and two lower ones called Ventricles.

The heart recieves blood into the the right atrium and from there it passes into the right ventricle. From the right ventricle it gets pumped to the lungs where the blood get oxygenated and carbon dioxide is expelled. The oxygen rich blood then comes back to the hart into the left atrium, passes through to the left ventricle from where it gets pumped out into the aorta and the rest of the body. Generally the ventricles have thicker muscle tissue surrounding them than the atria since they need to create a higher pressure to move blood into bigger circulatory systems. Similarly the left ventricle wall is thicker than the right one since the pressure needed to pump blood out into the aorta is greater than what's needed for the blood to reach the lungs. The atrium and ventricel of respective sides are separated by valves, to make sure blood does not flow in the wrong direction.