Chapter 20, Problem 1CYU

What structural features of capillaries make them well suited for their function of nourishing body tissues and removing waste products?

Summary Introduction

To review:

The characteristics of capillaries that enable them to nourish corresponding body tissues and to remove waste from them.

Introduction:

The human circulatory system is associated with the transportation of nutrients and gases throughout the body and it has a proper channel to perform this function. There are various structures associated with this channel and the smallest structures are known as the capillaries.

Explanation of Solution

The smallest blood vessels in the human body are capillaries with a diameter of 8 – 10 micrometers. The capillaries possess gaps of unjointed endothelial cells along with tight junctions. These gaps enable gaseous exchange and transportation across the capillaries. The gap junctions are of variable size and number in various kinds of capillaries enabling their proper functioning at respective locations.

Capillaries provide necessary nutrients and oxygen to the tissues and in turn eliminate carbon dioxide and nitrogenous waste products deposited in them. Some capillaries in the lungs enable oxygen to enter into the blood. Capillaries in small intestine receive the digested food. The capillaries present in the kidneys help to eliminate nitrogenous waste products.