blood vessels Flashcards
vessel wall contains large amount of elastic protein fibers
elastic arteries
tunica media consists of 6 or fewer layers of smooth muscle
arterioles
tiny vessels that connect arteries and veins
capillaries
take blood BACK TO the heart
- transport blood low in oxygen and high in carbon dioxide (exception: pulmonary veins)
- compared to arteries, their walls are much thinner and collapsible
- lumen generally much larger than arteries
- blood pressure is lower in veins
veins
take blood AWAY from the heart to other tissues
- transport blood high in oxygen (exception: pulmonary arteries)
- they have a relatively thick, springy wall
- blood pressure is higher in arteries than in veins
arteries
prevent backflow in veins
valves
outermost layer
- areolar connective tissue
- largest layer in veins
tunica externa
opening of veins
lumen
middle layer
- circularly arranged smooth muscle fibers
- largest layer in arteries
- sympathetic innervation typically causes vasoconstriction
tunica media
less elastic than elastic arteries, and more smooth muscle in the tunica media
muscular arteries
left and right brachiocephalic veins (head, neck, upper limbs)
superior vena cava
innermost layer
- endothelium (simple squampus epithelium) and areolar connective tissue
tunica intima
help blood be pushed in veins toward heart
skeletal muscle pumps
heart to elastic arteries to muscular arteries to arterioles to capillaries to venules to veins to heart
pathway of blood
coronary arteries (right and left)
ascending aorta
common site of venipuncture
median cubital vein
collect blood from capillaries
venules
brachiocephalic trunk
left common carotid artery
left subclavian artery
aortic arch
- vessel diameter is only slightly larger than the diameter of an erythrocyte
- have just a tunica intima
- gas/nutrient exchange occurs here
capillaries
- veins inferior to diaphragm including internal iliac veins, external iliac veins, common iliac veins
inferior vena cava
- subclavian artery
- axillary artery
- brachial artery
- radial artery
- ulnar artery
- superficial palmar arch
(deep veins have the same names as arteries) - superficial veins:
- cephalic vein
- basilic vein
- median cubital vein
upper limbs
- internal thoracic artery
- anterior intercostal artery
- posterior intercostal artery
- internal thoracic vein
- anterior intercostal vein
- azygos system:
- azygos vein
- hemiazygos vein
- (accessory hemiazygos vein)
- posterior intercostal vein
thorax
- internal iliac arteries
- external iliac arteries
common iliac arteries
- formed when venules unite
- most (but not all) have valves
veins
