Explanation

Capillaries are microscopic and smallest blood vessels. Their exceedingly thin walls consists of just a thin tunica interna. Most tissues have a rich capillary supply but cartilage and epithelia lack capillaries. Capillaries do not function independently, instead they tend to form interweaving networks called capillary beds. The true capillaries number 10 - 100 per capillary beds depending on the organs or tissues served.