What function do capillaries serve in the cardiovascular system?
a.
carry blood to the brain
b.
return blood to the lungs
c.
control body temperature
d.
replace old blood cells

Answer – B. (Return blood to the lungs)
  The function that capillaries serve in the cardiovascular system is to return blood to the lungs. The capillaries beds are the area where the excess carbondioxide produced by the cells are exchanged with oxygen. The deoxygenated blood is then transported by the capillaries through the circulatory system back to the lungs for reoxygenation

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