The muscular wall of the left ventricle is thicker than the right wall because it does what?
The answer has to do with the specific function of the the ventricles and where they are sending the blood to in the body. In the human body, the right atrium receives deoxygenated blood returning from the body. This blood goes from the right atrium to the right ventricle. When the right ventricle contracts, it sends the oxygen-poor blood to the lungs, which are relatively close to the heart. Not as much force is required for this short trip to the lungs, which probably accounts for the thinner ventricular wall on the right side. The now oxgenated, oxygen-rich blood returns from the lungs to the left atrium. The left atrium delivers the blood to the left ventricle, which contracts and sends the oxygen-rich blood to the rest of the body. This is a much longer trip and requires more force, which results in higher blood pressure in the aorta, the main artery coming out of the left ventricle. The need for more force to send the blood throughout the rest of the body results in the left side of the heart being more muscular, or thicker.