Question

The entry of the pulmonary veins into the adjacent veins is guarded by

• A. Haversian valve
• B. Thebesian valve
• C. Eustachian valve
• D. None of the above

Answer 1

The correct option is D None of the above

The entry of the pulmonary veins into the rest of the veins is not guarded by any valve.
The superior vena cava collects deoxygenated blood from the upper parts of the body (head and arms) and enters into the right atrium through the Haversian valve.
The inferior vena cava collects deoxygenated blood from the lower parts of the body and enters into the right atrium through the Eustachian valve.
The coronary sinuses collect deoxygenated blood from the heart walls and enter the right atrium through the Thebesian valve.