Emergency Medical Technician (EMT) Practice Test

What delivers blood to the right atrium?

1. The aorta

2. The carotid artery

3. The superior and inferior vena cava

4. The pulmonary vein

The correct answer is: The superior and inferior vena cava

The correct answer is the superior and inferior vena cava, which are large veins responsible for delivering deoxygenated blood from the body back to the right atrium of the heart. The superior vena cava collects blood from the upper parts of the body, such as the head, neck, arms, and chest, while the inferior vena cava gathers blood from the lower parts, including the abdomen and legs. This return route is essential for maintaining proper circulation and ensuring that blood can be reoxygenated in the lungs before being pumped out to the rest of the body. The aorta, by contrast, carries oxygenated blood away from the heart to the rest of the body, while the carotid artery specifically supplies blood to the head and neck and is a part of the arterial circulation. The pulmonary vein transports oxygenated blood from the lungs back to the left atrium of the heart, being part of the pathway that completes the pulmonary circulation. Therefore, only the superior and inferior vena cava are involved in returning deoxygenated blood directly to the right atrium.