Question

Blood vessels contain valves that prevent backflow under __ pressure while the heart contains valves that prevent backflow under __ pressure.

a) low, low

b) low, high

c) high, low

d) high, high

Answer 1

Answer

Blood vessels contain valves that prevent backflow under low pressure while the heart contains valves that prevent backflow under high pressure.

• Veins are the blood vessels that contains valves. The blood flows with very low pressure in the veins.
• In order to prevent backward flow of blood towards capillaries, veins contains valves.
• In heart there are four valves that prevent back flow of blood under high pressure.
• Atrioventricular valves prevent backflow into atria during ventricular contraction.
• Semilunar valves prevent backblow of blood during ventricular diastole to maintain high blood pressures in the great arteries.

Option B) low, high