Circulatory System Flashcards
Large arteries:
Medium arteries:
Elastic (conducting)
Muscular (distributing)
arteries that:
- contain more elastic fibers
- conduct blood from heart to medium-sized arteries
large arteries (elastic)
arteries that:
- have more smooth muscle and fewer elastic fibers
- distribute blood to body
- vasoconstrict and vasodilate
medium (muscular)
very small arteries that deliver blood to capillaries
arterioles
connect arterioles and venules
vessels for exchange of oxygen, nutrients, and waste
capillaries
Vessel tunics (3)
tunica intima
tunica media
tunica adventitia
vascular supply to large vessels
vasa vasorum
surround capillaries with arm-like processes
help control flow of blood through the capillary and exchange of materials
pericytes
3 types of capillaries
continuous
fenestrated
sinusoidal
capillaries with non-fenestrated endothelium
tightly controlled transport (found in BBB)
continuous
capillaries with fenestrated epithelium
found in renal glomerulus
fenestrated
capillaries with large lumen and leaky walls
found in spleen
sinusoidal
layers of heart wall (4)
endocardium
myocardium
epicardium
pericardial sac
path of conduction through heart
SA node –> R atrium walls –> AV node –> bundle of His –> R & L bundle branches –> Purkinje fibers –> ventricle walls
3 pairs of veins that bring blood to tubular (embryo) heart
vitelline veins
umbilical vein (1)
cardinal veins
remnants of cardinal veins form (5)
superior VC inferior VC left brachiocephalic azygos common iliac veins
remnants of vitelline vein form (2)
hepatic vein
hepatic portal vein
3 paired arteries in development
dorsal aorta
vitelline arteries
umbilical arteries
dorsal aorta fuse to form
abdominal aorta
vitelline arteris form (3)
celiac artery trunk
superior mesenteric
inferior mesenteric
umbilical arteries supply _______ to placenta and proximal parts become ________
deoxygenated
internal iliac arteries
late in week 3, _______ canalize to form two _________
angioblastic cords
endocardial tubes
when embryo undergoes lateral folding the endocardial tubes become
one heart tube
5 dilations that appear in heart tube (cranial to caudal)
truncus arteriosus bulbus cordis ventricle atrium sinus venosus
bend at junction of bulbus cordis and primitive ventricle that forms at 23 days
bulboventricular loop
what leads to folding of the heart tube?
faster growth of the ventricle and bulbus cordis
after heart folding, inflow is now _______ rather than _______ and outflow is now ______ rather than ________
posterior; caudal
anterior; cranial
blood flow through primitive heart
sinus venosus –> primordial atrium –> atrioventricular canal –> primordial ventricle –> bulbus cordis –> truncus arteriosus –> aortic sac –> aortic arches
sinus venosus becomes
coronary sinus and smooth inflow of RA
primordial atrium becomes
L auricle and rough part of RA
bulbus cordis becomes
conus arteriosus (RV) and aortic vestibule (LV)
truncus arteriosus becomes
aorta and pulmonary trunk
major points of atrial division
foramen primum - opening between common atrium
septum primum - first membrane to form
foramen secundum - develops from septum primum
septum secundum - grows to right side of septum primum; grows to form flap valve with septum primum
foramen ovale
fossa ovalis
flap valve that allows some fetal/embryo blood to bypass the RV
foramen ovale
left atrium forms from
incorporation of the pulmonary vein on the posterior surface of the left side of the primitive atrium
what fuses to form aorticopulmonary septum?
bulbar ridges and truncal ridges
bending of heart tube to the left instead of right
dextrocardia
bending of heart tube to left WITH abdomen mirror image
dextrocardia with situs inversus
heart partially or entirely exposed on surface of thorax
ectopia cordis
most common atrial septal defect
patent oval foramen (foramen ovale remains open)
results from failure of ridges and aorticopulmonary septum to develop normally.
most common is a single arterial trunk
persistent truncus arteriosus
(VSD always accompanies)
4 defects of tetralogy of fallot
VSD
pulmonary stenosis
overriding aorta
RV hypertrophy
edges of aortic valve fuse to form a dome, causing a heart murmur
aortic valve stenosis
aortic blood shunted in pulmonary artery
patent ductus arteriosus
fetal circulation
umbilical vein (oxy blood to heart) –> ductus venosus (shunt around liver to connect IVC) –> foramen ovale (shunt from RA to LA) –> ductus arteriosus (from pulm arteries to aorta) –> umbilical arteries (2) (from descending aorta to placenta)
umbilical vein forms
ligamentum teres
ductus venosus forms
ligamentum venosum (round ligament of liver)
foramen ovale forms
fossa ovalis
ductus arteriosus forms
ligamentum arteriosum
umbilical arteries form
medial umbilical ligaments