Blood Vessels Flashcards
This type of smooth muscle cells regulate blood flow from thoroughfare channel into capillaries
precapillary sphincters
Inner layer of blood vessel that has endothelium, basement membrane, lamina propria, internal elastic membrane
tunica intima
3 main types of blood vessels
arteries, veins, capillaries
this is the function of most arteries
transport O2 rich blood away from heart
this is the function of most veins
moving O2 poor blood towards heart
smaller blood vessels that run in between veins and arteries
capillaries
First branch from the aortic arch is
brachiocephalic
these blood vessels are strong and elastic to account for the high-pressure blood they transport
arteries
three layers of artery wall
- tunica interna (inside)
- tunica media (middle)
- tunica externa (outside)
this arterial layer is thick and made of smooth muscle
tunica media
this arterial layer is thin, made of connective tissue and connects the artery to the surrounding tissues
tunica externa
What are arteries innervated by, and what kind of impulses do they carry?
vasomotor fibers; sympathetic
How do vasomotor fibers help to regulate blood pressure?
stimulation causes vasoconstriction, inhibition causes vasodilation
divisions of arteries are called
arterioles
as arterioles approach capillaries their walls get
thinner
small arterioles have the same layers as an artery except
only one layer of cells for each
these are the smallest blood vessels
capillaries
the only layer in capillaries
endothelium
what happens in capillaries?
substance exchange
exchange from inside capillaries to outside is called
filtration
exchange from outside capillaries to inside is called
absorption
in blood flow, where does filtration happen and what drives it?
arteriolar end of capillary, hydrostatic pressure (blood pressure > colloid osmotic pressure)
what is hydrostatic pressure driven by?
blood pumping
what is colloid osmotic pressure driven by?
plasma proteins drawing water into capillaries
where does absorption happen and what is it driven by?
venular end of capillaries, colloid osmotic pressure (COP > CP)
______ fluid leaves capillaries than returns via osmosis
more
what picks up excess fluid from capillary exchange and returns it to circulation?
lymphatic vessels
what goes from the capillaries into the surrounding tissues?
nutrients, oxygen
what cannot diffuse into surrounding tissues from the blood because they’re too big?
proteins
what gets absorbed from tissues into capillaries
CO2 and wastes
how do substances get in and out of capillaries?
slits between cells
these are connecting structures from capillaries to veins
venules
what are the four ways the walls of veins are different from the walls of arteries?
- Muscle layer thinner
- Have valves to prevent backflow of blood
- Lumens are larger
- Diameters thicker
veins also serve as __ ___, useful when a person is losing blood
blood reservoirs
what type of tissue is a capillary?
squamous epithelium
blood leaves the heart through the ___
aortic arch
if an artery is about to divide and keep its same name, it is called ___
common
The __ __ ___ vein is right next to the common carotid
right internal jugular
The __ ___ are large veins throughout the skull
venous sinuses
what are the seven arteries in the cerebral arterial circle?
Communicating - 2
Cerebral - 3
Carotid - 1
Basilar - 1
- anterior communicating
- internal carotid
- basilar
- posterior cerebral
- posterior communicating
- middle cerebral
- anterior cerebral
what is the longest vein in the arm and where is it?
basilic, proximal
what is the main artery of the abdominal cavity?
aorta
what vein runs in a similar position to the aorta in the abdominal cavity?
inferior vena cava
how many main iliac arteries/veins are there?
3 - common, external and internal
