what are capillaries . why do yhey have thin walls
- Capillaries are the smallest blood vessels which are present inside the tissues that exchange blood between arteries and veins. Also Oxygen, carbon dioxide, nutrients and wastes are exchanged through the thin walls of the capillaries between blood and tissues.
- They have very small diameter and have very thin walls through which material can easily move. Capillaries act as a link between arteries and veins.