Lect. 14 - systemic circulation Flashcards
arteries that carry blood from the heart to other organs
conducting arteries
arteries that divide into medium-sized with high elastin component dampens the BP from heart contractions
distributing arteries
charact. of arterioles
smaller arteries
divisions of medium-sized arteries
divide into capillaries
function of arterioles
control the vasoconstriction/vasodilation
where substances are exchanged between blood and body tissues
groups unite to form small veins called venules
large enough for 1 erythrocyte at a time
capillaries
merging of venules forming large blood vessels
carry blood from tissues back to the heart
veins
vaso vasorum other name
vasculature of vessels
function of vaso vasorum
located in the walls of larger blood vessels
supply oxygen and nutrients to those larger blood vessels
3 layers of the artery walls
tunica interna
tunica media
tunica externa
which layer is closest to the lumen
tunica interna
which layer is the thickest, highly elastic
tunica media
which layer is made of elastin and collagen fibers
tunica externa
tunica interna
smooth surface, prevents friction
tunica media
smooth muscle - vasoconstriction/vasodilation
tunica externa
protects vessels, anchors it to surrounding structures
roles of arterioles (2)
Play a key role in regulating blood flow into capillaries
Change in diameter also affects blood pressure
“resistance vessels”
arterioles
“exchanging vessels”
capillaries
capillaries
extensive network in muscles, liver, kidneys and nervous system
none are found in the lining epithelia, cornea, lens and cartilage
t/f capillaries have a tunica externa and media
nope
1 metarteriole supplies ___ capillaries (capillary bed)
10-100
venules
union of several capillaries
collect blood from several capillaries and drain into the veins
t/f veinules have no tunica externa
true
t/f veins can withstand high pressures
false
t/f veins have tunica externa, interna, media
true
pumping of venous blood back to the heart is done through: (3)
- pumping of the heart
- contraction of skeletal muscles in lower limbs
- valves found in the veins
charac. of venous valves
each valve has 2 or more folds of tunica interna forming cusps projecting towards the heart
leaky venous valves results in ___
varicose veins (swollen veins)
at rest
- veins/venules
- capillaries
- arteries/arterioles
- remaining 20%??
60% of BV
5% of BV
15% of BV
systemic circulation includes (4)
cerebral circulation
portal system
all arteries branching from the aorta
all veins draining into the SVC, IVC, coronary sinus
name the arteries of the head and neck (3 branches)
brachiocephalic
subclavian
common carotid
2 branches from subclavian a.
vertebral artery
internal mammary - ant. intercostals
2 branches from common carotid a.
internal carotid (circle of willis, opthalmic) external carotid
7 divisions from external carotid from inf. to sup.
sup. thyroid lingual facial occipital posterior auricular maxillary superficial temporal
major source to deep skull, orbit, teeth, muscles of mastication, dura mater
maxillary a.
2 branches from maxillary a.
infraorbital
middle meningeal
4 branches from superficial temporal a.
zygomatico-orbital
transverse facial
frontal
parietal
thoracic aorta branches into (1)
posterior intercostal
thoracic aorta continues until it passes through the diaphragm and becomes ___
abdominal aorta
2 divisions of abdominal arteries
celiac trunk
superior mesenteric
3 branches from celiac trunk
left gastric
splenic
common hepatic
what does the sup. mesenteric supplies in general
most of the intestines, head of pancreas
what is supplied by these arteries:
- celiac trunk
- inferior phrenic
- suprarenal
- renal
- GI tract, spleen
- diaphragm
- suprarenal glands/adrenal
- kidneys
what is supplied by these arteries:
- superior mesenteric
- testicular/ovarian
- inferior mesenteric
- common iliac
- GI tract
- gonads
- GI tract
- lower extremities (EI) and pelvis/perineum (II)
supplies stomach, duodenum, pancreas, greater omentum
gastroduodenal
supplies stomach and esophagus
gastric
supplies liver, gallbladder, stomach
common hepatic
supplies stomach, greater omentum
gastroepiploic (gastro-omental)
drains neck and upper limb
drains intercostal and lumbar regions by a collection of veins
SVC
collection of veins that drains the intercostal and lumbar region
azygos system
no major veins draining the GI tract, gall bladder, and pancrease, they have their own ___
portal system
liver is drained by ___ into the IVC
hepatic veins
testicular/ovarian drain into the IVC on ___ side only, __ side drains into renal vein
right, left
connects IVC and SVC as an alternative pathway
azygos system
role of portal system (3)
- detours blood from the GI organs and spleen through the liver before going into the IVC
- carries blood from one capillary network to another without going to the heart
- rich in substances after a meal
t/f pulmonary artery carries oxygenated blood
false, even if it’s blue, carries deoxygenated blood from R ventricle to air sacs in the lungs
t/f pulmonary vein carries oxygenated blood
true, even if its red
4 things happening in the pulmonary circulation (CO2, O2, transport, ejection)
- Co2 passes into alveoli (exhaled)
- inhaled O2 from air to blood
- pulmonary veins transport oxygenated blood to the L atrium
- blood is ejected into the systemic circulation
t/f arteries are less elastic, have thinner walls and are larger in diameter
true
peak systolic pressure in the R ventricle is __% of the peak systolic pressure in the L ventricle
20%
pulmonary edema
reduces rate of diffusion of O2/CO2 this slows down the exchange of respiratory gases in the lungs
t/f lungs, kidneys and GI tract function way before birth
false, they do not function until after birth
fetal circulation occurs through the ____ with ___ and ____
placenta with foramen ovale and ductus arteriosus
after birth, the umbilical cord becomes a fibrous cord called the _____
medial umbilical ligament
after birth, umbilical vein becomes ___
ligamentum teres
after birth, ductus venosum becomes ___
ligamentum venosum
2 things form after birth
fossa ovalis
ligamentum arteriosum
