What are the main heart valves?

The main heart valves consist of the mitral valve, tricuspid valve, aortic valve, and pulmonary valve. Each of these valves plays a crucial role in the proper functioning of the heart by ensuring unidirectional blood flow and preventing backflow during the cardiac cycle.

The aortic valve is located between the left ventricle and the aorta, preventing blood from flowing back into the ventricle after it is pumped out to the body. The pulmonary valve is found between the right ventricle and the pulmonary artery, stopping blood from returning to the ventricle after it has been sent to the lungs for oxygenation. The mitral valve, situated between the left atrium and the left ventricle, allows blood to flow from the atrium to the ventricle while preventing backflow when the ventricle contracts. Similarly, the tricuspid valve is located between the right atrium and right ventricle, ensuring blood moves in the correct direction during the heart's pumping cycle.

In contrast, the other options do not pertain to the heart valves. The option mentioning left and right atria refers to the chambers of the heart, not valves. The choice including the sinus node and AV node refers to specialized