Permitting the passage of nutrients and gases between the blood and tissue cells is the primary function of capillaries. They are tiny blood vessels.
Capillaries are tiny blood vessels of the circulatory system, which is one of the major organ systems.
The primary function of capillaries is to transport nutrients and oxygen (red blood cells) to all cells of the body.
Capillaries represent the smallest vessels found in the circulatory system (they have 5 to 10 μm in diameter).
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