heart development Flashcards
general overview of heart development
- cardiac crescent (contains primary heart field)
- heart tube
- pre-septated looped heart
- four chambered heart
progenitor heart cells migrate through primitive streak into the:
splanchnic layer of lateral plate mesoderm
1st sign of heart formation is a solid, ____ shaped cluster of cells called the ______
horseshoe; primary heart field
once cells establish the primary heart field, they are induced by underlying ____ to form ____ and blood islands and vessels by the process of _____
endoderm; cardiac myoblasts; vasculogenesis
blood vessels arising from blood islands; mesoderm cells > hemangioblasts > tube formation; formation of blood vessels de novo (embryonic process)
vasculogenesis
blood vessels sprouting from existing vessels
angiogenesis
islands will unite and form a horseshoe-shaped _____ lined tube surrounded by ____ within the ____ region; these are called _____ tubes
endothelial; myoblasts; cardiogenic; endocardial
other blood islands appear bilaterally which will form the pair of longitudinal _____
dorsal aortae
the lateral sides of the horseshoe shaped endothelial tube fold in ____ and ____, approaching eachother at the midline to fuse, forming a single ____
ventrally; medially; primordial heart tube
_____ creates primordial heart tube
lateral body folding
due to rapid neural tube growth, embryo also undergoes _____ folding or ____ folding
cranial to caudal folding; sagittal
cranial-caudal folding ____ the developing heart and _____
repositions; pericardial cavities
initially, the heart tube is attached to the dorsal side of the pericardial cavity via ____
dorsal mesocardium
the middle section of the dorsal mesocardium will disappear and create the _____
transverse pericardial sinus
dilations of the heart tube from caudal to cranial
- sinus venosus
- primordial atrium
- primordial ventricle
- bulbus cordis (conus cordis + truncus arteriosus)
where rhythmic contractions of the heart tube become organized
sinoatrial canal
the myocardial tissue in the sinoatrial canal gives rise to the ____ and ____
sinoatrial and atrioventricular nodes
usually days ____ correlate with the first heart beat
22/23
sinus venosus becomes:
coronary sinus and sinus venarum
primordial atrium becomes:
right and left auricles + portions of the atria
primordial ventricle becomes:
left ventricle
conus cordis becomes:
outflow tract of ventricles; caudal portion of bulbus cordis forms right ventricle
truncus arteriosus becomes:
pulmonary trunk and aorta
____ will connect to dorsal aortae
pharyngeal arch aa.
primitive ventricles move ___ and to the ____ while atrial region moves ____ and to the ____
ventrally; right; dorsally; left
sinus venosus receives venous blood from 3 paired veins:
- vitelline vv.
- umbilical vv.
- common cardinal vv.
left sinus horn becomes:
- oblique veins of the L atrium
- coronary sinus
right sinus horn entrance into the right atrium is called the ____, flanked by ____
sinuatrial orifice; right and left venousvalves
when right sinus horn is incorporated into the wall of the right atrium it is called ____
sinus venarum
inferior portion of right valve becomes:
- valve of IVC
- valve of coronary sinus
near end of week 4, _____ form on each side of chamber plus one on dorsal and ventral walls of AV canal
four atrioventricular (AV) endocardial cushions
fusion of these cushions results in complete division of:
AV canal into and left and right
around end of week 4, crest of tissue grows from roof of common atrium called ____
septum primum
opening below the septum primum and endocardial cushions is the ____
ostium primum
cell death produces perforations in ____ which coalesce to form ____
septum primum; ostium secundum
As holes in the septum primum coalesce to form the ostium secundum, a thicker _____ develops from the roof of the _____, slightly to the ____ of the septum primum
septum secundum; primordial atrium; right
septum secundum grows inferiorly and develops an opening:
foramen ovale
After birth, the pressure in the left atrium increases as the blood returns from the lungs.
_____ is pressed against the ______ and adheres to it, permanently closing the ____ and forming the _____
septum primum; septum secundum; foramen ovale; fossa ovalis
End of week 4, primitive ventricles begin to expand;
Medial walls will merge together to form the _____ with ____ located above it
muscular interventricular septum; interventricular foramen
outgrowth of the _____ closes the interventricular foramen; complete closure forms the ____
inferior endocardial cushion; membranous part of the interventricular septum
during week 5, neural crest cells migrate into ____ and ____, forming ____ and ____
migrate into truncus arteriosus and bulbus cordis; form truncal ridges and bulbar ridges
Ridges undergo a ____ spiraling which results in the formation of a ______when the ridges fuse
180 degree
spiral aorticopulmonary septum
ridges also grow ____ to contribute to ____
inferiorly; membranous interventricular septum
