Which statement about the right atrium is true?

Which statement about the right atrium is true?

• A. It receives blood from the lungs first
• B. It receives blood from the body first
• C. It pumps blood to the brain
• D. It carries oxygenated blood to the body

Answer: (B)

The right atrium is the receiving chamber for deoxygenated blood returning from the body. Blood from the systemic veins — via the superior and inferior vena cavae (and the coronary sinus draining the heart muscle) — first flows into the right atrium. From there, it moves to the right ventricle and then to the lungs for oxygenation. It does not receive blood from the lungs (that’s the left atrium) and it does not pump oxygenated blood to the brain or to the body (that’s the role of the left-sided chambers and the aorta). So the statement that the right atrium receives blood from the body first accurately reflects the circulation sequence.

The right atrium is the receiving chamber for deoxygenated blood returning from the body. Blood from the systemic veins — via the superior and inferior vena cavae (and the coronary sinus draining the heart muscle) — first flows into the right atrium. From there, it moves to the right ventricle and then to the lungs for oxygenation. It does not receive blood from the lungs (that’s the left atrium) and it does not pump oxygenated blood to the brain or to the body (that’s the role of the left-sided chambers and the aorta). So the statement that the right atrium receives blood from the body first accurately reflects the circulation sequence.