Ch 4 Vascular Anatomy Flashcards
What are the 3 layers of a vessel
tunica intima
tunica media
tunica adventitia
What does the tunica intima consist of
endothelial cell lining with connective tissue beneath
What is the thickest component of the vessel wall
tunica media
What is the tunica media composed of
smooth muscle and varying amounts of elastic fibers and collagen
What is the tunica adventitia composed of
connective tissue
nerve fibers
small capillaries
What are arterioles called and why
“stopcocks” because the circular smooth muscle layers control contraction and resistance
What are the small and medium sized arteries
all except aorta and major branches
What diameter are small to medium arteries and what are the composed of
4mm
smooth muscle layers
what are large arteries composed of
less smooth muscle which makes them elastic
What are the differences between the vein and artery layers
veins are not as muscular
veins walls are thinner
veins have more elastic fiber and collagen
vein thickness depends on region of body
what are venules mainly composed of
connective tissue
what are small to medium sized veins
all veins except portal vein, vena cava and their main branches
what is the diameter of small to medium veins
1-10 mm
what are the large veins
portal vein
SVC
IVC and main branches
What region of the body will veins be thinner and why
proximal to the heart because of the heart’s contraction
What is unique about veins
they have a bicuspid valve with two leaflets that prevent backflow of blood
Where are these veins with valves located
lower extremity
What is the smallest vessel in the body
capillaries
What are capillary walls composed of
layer of endothelial cells
What happens in the capillary
waste, CO2, nutrient exchange
Which carotid artery rises directly from the aorta
left
Which carotid originates from brachiocephalic artery
right
where does the ICA lay in relation to the ECA
lateral
What do ECAs have that ICAs do not
extracranial branches
Intra cranial segment consists of what three portions
petrous
cavernous
cerebral
Where does the ECA lay in relation to the ICA
medial
What does the ECA normally supply
neck and face
What does the ICA normally supply
brain
How many branches does the ECA have
8
Where do vertebral arteries arise from
subclavian
What do vertebral arteries pass through
transverse processes of cervical vertebrae
Where do the vertebral arteries enter the skull
foramen manum
When the vertebral arteries connect, what is this vessel called
basilar artery
What forms the circle of willis
branches of ICA and vertebral arteries
What does the ICA terminate into
anterior cerebral
middle cerebral
posterior communicating
anterior choroidal
What are the anterior cerebral arteries connected through
anterior communicating artery
What completes the circle of willis by connecting right and left sides
anterior and posterior communicating arteries
Where does the external jugular drain from
cranial cavity, neck and face
Where does the external jugular drain into
subclavian
Where does the internal jugular drain from
brain
How does the internal jugular run in relation to the ICA and CCA
anterolateral
The internal jugular unites with _____ to form ______
subclavian vein
brachiocephalic vein
At what level do the vertebral veins emerge
6th cervical vertebra
What do the vertebral veins empty into
brachiocephalic vein