Blood is pumped at high pressures in arteries from the heart to ensure that all parts of the body receive adequate blood flow.Capillary beds,however,would hemorrhage under direct arterial pressures.How does the design of the circulatory network contribute to reducing blood pressure to avoid this scenario?
A)Blood flow through the capillaries is essentially frictionless,and this reduces the amount of pressure on their walls.
B)The total cross-sectional diameter of the arterial circulation increases with progression from artery to arteriole to capillary,leading to a reduced blood pressure.
C)Fluid loss from the arteries is high enough that pressure drops off significantly by the time blood reaches the capillaries.
D)All of the above answers apply.

Question

Quizplus · Accepted Answer

The total cross-sectional diameter of the arterial circulation increases with progression from artery to arteriole to capillary, leading to a reduced blood pressure. This is known as the arteriolar resistance, and it allows for a controlled reduction in pressure to prevent capillary hemorrhage. Option A is incorrect because while blood flow through the capillaries is essentially frictionless, this does not reduce the amount of pressure on their walls. Option C is also incorrect because fluid loss from the arteries does not drop off significantly enough to prevent capillary hemorrhage. Option D is incorrect because option A and C are incorrect.

Blood Is Pumped at High Pressures in Arteries from the Heart