BLOOD VESSELS
1
, Major blood vessels
• Five:
– Arteries and arterioles carry blood away
from heart
– Veins and Venules return blood to heart
– Capillaries site of exchange
2
,Structure of blood vessels
• Walls consist of 3 layers:
– Tunica intima
– Tunica media
– Tunica externa
3
, Tunica interna/intima
• Forms inner lining
• In contact with blood
• Consists of :
– a single squamous epithelium-endothelium
– Basement membrane-supports the
epithelial layer
– Internal elastic lamina-thin sheet of
elastic fibers
4
1
, Major blood vessels
• Five:
– Arteries and arterioles carry blood away
from heart
– Veins and Venules return blood to heart
– Capillaries site of exchange
2
,Structure of blood vessels
• Walls consist of 3 layers:
– Tunica intima
– Tunica media
– Tunica externa
3
, Tunica interna/intima
• Forms inner lining
• In contact with blood
• Consists of :
– a single squamous epithelium-endothelium
– Basement membrane-supports the
epithelial layer
– Internal elastic lamina-thin sheet of
elastic fibers
4
