The heart is basically the pump of the circulatory system. The left side of the heart has the left atrium and left ventricle. The right side of the heart has the right atrium and right ventricle. Here is a very simplified version of how the heart pumps blood:
- Oxygenated blood flows through the pulmonary veins and the blood directly enters into the left atrium.
- The blood then travels through a valve called the left artioventricular (bicuspid) valve, and enters the left ventricle.
- The ventricle then contracts and forces the blood into the aorta.
- The aorta closes off due to a valve called the aortic semi-lunar valve.
- There are numerous arteries from the aorta that carry oxygenated blood to the body. The blood that flows into the arterial system returns to the right side of the heart.
- The superior vena cava and the inferior vena cava dump the deoxygenated blood into the right atrium.
- The blood passes into the right ventricle via the right atrioventricular (tricuspid) valve.
- The right ventricle contracts and the blood enters another valve called the pulmonary semi-lunar valve, then enters the pulmonary artery, which branches out into arteries that take deoxygenated blood to the lungs.
- During this entire process the heart relaxes and contracts in order to move the blood through.
Blood is drained from the head and neck into the right atrium (RA) via the superior vena cava(large vein). Blood returns from the rest of the body to the RA via the inferior vena cava(another large vein). From the RA blood passes through the tricuspid valve into the RV, right ventricle. It then travels to the lungs via the pulmonary arteries. It leaves the lungs after picking up oxygen and dropping off carbon dioxide. Now it enters the LA, left atrium and goes through the bicuspid valve(mitral valve) into the LV, left ventricle. From here it enters the arch of the aorta(aortic arch) and passes through the aorta(largest artery in your body) and passes through the thoracic aorta, then abdominal aorta, then splits into two bilateral iliac arteries into femoral arteries in the thigh.
Heart is an organ in humans and many other well developed animals that pumps blood in the body for circulating it in all parts of the body. It is actually a pair of two pumps incorporated in large, hollow muscular organ.T
Veins carries blood from throughout the body to the heart and empties it in the right-sided pump. The heart then pumps this blood to the lungs. In the lungs the blood picks up oxygen and releases carbon dioxide collected from the body. This purified and oxygen rich blood then flows to the left side of the heart, Now the heart pumps this blood through arteries to the rest of the body.