What is the valve that prevents backflow of blood from the right ventricle into the right atrium?

• A. Bicuspid (Mitral) Valve
• B. Aortic Valve
• C. Tricuspid Valve
• D. Pulmonary Valve

Answer: (C)

The key idea is how valves control the direction of blood flow between heart chambers. The valve between the right atrium and the right ventricle is the right atrioventricular valve, which prevents blood from flowing backward into the atrium when the right ventricle contracts. This valve is called the tricuspid valve because it has three leaflets (cusps).

Understanding the others helps place it in context: the mitral (bicuspid) valve sits between the left atrium and left ventricle; the aortic valve sits at the exit of the left ventricle into the aorta; and the pulmonary valve sits at the exit of the right ventricle into the pulmonary artery. Only the right-sided atrioventricular valve stops backflow into the right atrium, making the tricuspid valve the correct choice.