What function do capillaries serve in the cardiovascular system?
A.
carry blood to the brain
B.
return blood to the lungs
C.
help control body temperature
D.
replace old blood cells

Please select the best answer from the choices provided.

A
B
C
D

The capillaries help in controlling the body temperature.

Further Explanation:

Capillaries are the thinnest blood vessels in the circulatory system. The primary function of a capillary is exchange of gases. The tissues of kidney, muscles and liver have the abundance of capillaries. The metabolic activity of a tissue decides the amount of capillaries in the tissue. The function of capillaries may include pinocytosis andpassive diffusion.

There are different kinds of capillaries:

Continuous capillaries are the capillaries in which the endothelial cells have gaps in the middle of them that allow diffusion of water, sugar, hormones and gases to pass through. The blood-brain barrier is an exception.

Fenestrated capillaries are the capillaries which are "leakier" than continuous capillaries. Small pores along with the small gaps between the cells are present in these capillaries. Small intestine and kidneys are typically composed of fenestrated capillaries.

Sinusoid capillaries are the “leakiest" capillaries that helps the transport of large molecules such as cells. The liver, spleen and bone marrow causes disease kind of capillaries.

The temperature of the body can be maintained by the capillaries as their present near the surface of the skin. When the temperature of the atmosphere is too low, the capillaries undergo vasoconstriction which means the decrease in the diameter of the capillaries. This vasoconstriction leads to the decrease in blood flow near the surface of the skin eventually leading to the loss of heat via radiation. When the temperature of the atmosphere is too high, the capillaries undergo vasodilation which means that the diameter of the capillaries increases and does increases the loss of heat via radiation