Which valve prevents backflow from the left ventricle into the left atrium?

Which valve prevents backflow from the left ventricle into the left atrium?

• A. Aortic valve
• B. Tricuspid valve
• C. Mitral valve (bicuspid)
• D. Pulmonary valve

Answer: (C)

This question tests understanding of how heart valves prevent backflow between chambers. The valve between the left atrium and left ventricle is the mitral valve, also called the bicuspid valve. It stays closed when the left ventricle contracts to stop blood from flowing backward into the left atrium, and it opens when the ventricle relaxes to allow filling from the atrium. The aortic valve sits between the left ventricle and the aorta and prevents blood from flowing back into the ventricle; the tricuspid valve lies between the right atrium and right ventricle; the pulmonary valve sits between the right ventricle and the pulmonary artery.

This question tests understanding of how heart valves prevent backflow between chambers. The valve between the left atrium and left ventricle is the mitral valve, also called the bicuspid valve. It stays closed when the left ventricle contracts to stop blood from flowing backward into the left atrium, and it opens when the ventricle relaxes to allow filling from the atrium. The aortic valve sits between the left ventricle and the aorta and prevents blood from flowing back into the ventricle; the tricuspid valve lies between the right atrium and right ventricle; the pulmonary valve sits between the right ventricle and the pulmonary artery.