The ventricle is the lower part of the heart that plays a big role in the circulatory system of the human body. It is divided into two chambers, the left and the right ventricles. Although both belong to the lower part of the heart, each one has different functions in the collection and distribution of blood into the bloodstream.
Definitions

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The right ventricle receives deoxygenated blood from the right atrium through the tricuspid valve and pumps it to the main pulmonary artery. The pulmonary artery, which extends from the right ventricle, further branches out to the left and right pulmonary arteries. By circulating into the pulmonary arteries, the deoxygenated blood picks up oxygen from the lungs before it circulates to the left atrium.
The left ventricle receives the oxygen-rich blood from the left atrium by passing through the mitral valve, and pumps it to the aorta. Through the aorta, the oxygenated blood is distributed to other parts of the body through systemic circulation.
During ventricular diastole (the phase of the heartbeat when the heart muscle relaxes), the ventricular muscles relax to let the entry of blood into the chambers. Through this process, the oxygenated blood from the left atrium enters the left ventricle while deoxygenated blood from the right atrium enters the right ventricle. During ventricular systole (the phase of the heartbeat when the heart muscle contracts and pumps blood), the ventricular muscles contract to pump blood out of the chambers. The left ventricle contracts to pump out blood to the systemic circulation while the right ventricle contracts to pump out blood to the pulmonary circulation for oxygenation.
Left ventricle Vs Right Ventricle
What is the difference between left and right ventricle? It is easy to remember by understanding the nature of the action of each chamber. Keep in mind that the left ventricle is responsible for the distribution of blood to the rest of the body through the aorta, while the right ventricle is responsible for the distribution of blood to the pulmonary arteries.
The left and right ventricles are equal in size and pumping volume. However, the left ventricle has thicker walls than the right since it needs to pump blood to the rest of the body. The right ventricle has thick walls at the base but gradually thins out upward towards the atrium.
The left ventricle receives only oxygenated blood from the left atrium through the mitral valve. The oxygenated blood come from the pulmonary circulation. The right ventricle receives only deoxygenated blood from the right atrium through the tricuspid valve. The deoxygenated blood came from the systemic circulation through the inferior and superior vena cava.
Comparison Chart
Left Ventricle | Right Ventricle |
Receives oxygenated blood from the left atrium through the mitral valve | Receives deoxygenated blood from the right atrium through the tricuspid valve |
Pumps blood to the systemic circulation through the aorta | Pumps blood to the pulmonary circulation through the pulmonary arteries |
Has thicker walls than the right ventricle | Has thinner walls than the left ventricle |
Oval in shape, forming the apex of the heart | Triangular in shape, located near the apex of the heart |