1. Blood Vessels
Gross Anatomy

2. Blood Vessels Vascular system Arteries Arterioles
Closed transportation system for the blood
Arteries
Leave heart
Carry oxygen (except pulmonary artery!)
Arterioles
Branches from arteries
Form networks in capillaries

3. Blood Vessels Capillary beds Venules Veins
Network connection between arteries and veins
Supply oxygen to tissues
Venules
Branches of veins
Found in capillary beds
Veins
Return to heart
Carry carbon dioxide (except pulmonary vein)

4. Microscopic Anatomy 3 wall coatings of most vessels Tunic intima
Internal slick surface
Tunic media
Middle coat
Smooth muscle
Elastic tissue fibers
Tunic Externa
Outermost covering
Fibrous connective tissue for support and protection

5. Structural Differences
Veins
Under low pressure (flow against gravity)
Shallow
Larger valves
Arteries
Thicker walls, higher pressure
Deep, protected
Both arteries and veins usually follow a similar path
Skeletal muscle contributes to venous return
“milking” of veins to push up, Valves prevent backflow

6. Capillaries ONE layer thick (tunica intima)
Allows for easy gas exchange
Forms a bed or network
Microcirculation
Two types of vessels in capillary beds
Vascular shunt
Connection point between arteriole and venule
True capillary
Exchange gases with tissues and vessels
10 to 100 per capillary bed

7. Gross Anatomy Aorta Branches into other aortic arteries Largest artery
Size of garden hose
Leaves left ventricle of heart
Branches into other aortic arteries
Ascending aorta
Arches to left (aortic arch)
Then continues into thorax, through diaphragm, into abdominal cavity to become abdominal aorta

8. Aortic Branches Ascending aortic Aortic Arch
Left and right coronary arteries
Supply heart with blood
Aortic Arch
Brachiocephalic trunk
branches into
R. Carotid/ R. Subclavian
L. Carotid supplies brain, head, neck
L. Subclavian
Branches into
Vertebral arteral (brain)
Axillary artery to brachial artery

9. Aortic Branches Thoracic Aorta branches into Supplies thoracic region
Intercostal
Bronchial
Esophageal
Phrenic (diaphragm)
Supplies thoracic region

10. Aortic Branches Abdominal aorta Celiac trunk Superior mesenteric
Hepatic, gastric, splenic arteries
Superior mesenteric
small/large intestine
Inferior mesenteric
Lg intestine
Common iliac
Final branches
Lower body

11. Major Veins
Veins return deoxygenated blood to the heart through the venae cavae
Superior (upper body)
Inferior (lower body)
Named same way as arteries
Location
Organ served
Great Saphenous
Longest vein in body, legs