Question

Blood pressure in the pulmonary artery is
(a)Same as that in the aorta
(b)More than that in the carotid
(c)More than that in the pulmonary vein
(d)Less than that in the venae cavae

Answer 1

Arteries are the blood vessels that carry blood from the heart to the different organs, whereas veins are the vessels that carry blood from different parts of the body back to the heart. Generally, veins have valves to prevent the backflow of the blood.

Complete answer:
Pulmonary arteries are the arteries that carry deoxygenated blood from the heart to the lungs for oxygenation. The blood in the pulmonary arteries is pumped by the right ventricle of the heart.
Pulmonary veins carry oxygenated blood from the lungs back to the heart and enter the left atrium.
Since the blood in the pulmonary arteries is pumped by the heart, it flows under greater pressure than the blood in the pulmonary veins.
The pulmonary artery pressure or PA pressure is the measure of the blood pressure seen in the pulmonary artery and is measured by inserting a catheter into the artery.
So, the correct answer is, “More than that in the pulmonary vein”

Note: -Usually, the arteries carry oxygenated blood and veins carry deoxygenated blood. The pulmonary vessels and the umbilical vessels are the only exceptions to it.
-The blood in the veins flows under low pressure, hence the vessel walls have valves that prevent the backflow of blood.
-Since, the blood flow in the veins is not under pressure, the lumen is thin and the walls are rigid.
-The instrument used to measure blood pressure is known as the sphygmomanometer.