Development of the Heart (Exam 2) Flashcards
What is the function of the post-natal CV system
deliver blood to lungs for oxygen and distribute oxygenated blood throughout body
What is the function of embryonic/fetal cardovascular system
blood receives O2 from placenta, lungs are still developing
How is the primary heart field formed
Cardiac progenitor cells migrate into splanchnic mesoderm
Where do cardiac progenitor cells come from
epiblast
Where do the cardiac progenitor cell migrate
cranial to oropharyngeal membrane
How is the cardiagenic area formed
primary heart field cells form cardiac myoblasts and blood islands
What induces the PHF cells to form cardiac myoblasts and blood islands
underlying endoderm
How is the heart tube formed
embryonic folding brings heart tube into position in the thorax and causes fuse of PHF together
How is the transverse pericardial sinus formed
breakdown of the dorsal mesentery that held the heart suspended
What is the heart surrounded by
pericardial cavity
How will the heart tube receive and expel blood
receives blood at the caudal end and expels blood from the rostral end
What layer is the pericardial cavity associated with in the embryo
endoderm
What are the layers of the heart tube
endocardium
myocardium
epicardium
Where does the endocardium come from
layer of endothelial cells that line inner aspect of the tube
what is the myocardium
muscle, bulk of tube
what is the epicardium
outer line, synonymous with visceral layer of serous pericardium
What are the parts of the heart tube
bulbis cordis
primordial ventricle
primordial atrium
sinus venous
What are the parts of the bulbis cordis
truncus arteriosus
conus cordis
primitive right ventricle
What is the bulbs cords associated with
outflow on cranial end
What veins will drain into the sinus venosus
vitelline umbillical common cardinal vein coronary sinus sinus venarum oblique vein of left atrium
What is the sinus venarum
smooth region in the right atrium that receives blood from the vena cava and the coronary sinus
Where is the sinus centrum found
in the posterior part of the right atrium
When and why will the heart tube form a loop
4th week due to differential growth
How does the heart tube form a loop
bulbis cordis moves anteriorly, inferiorly and to the right side
ventricle moves anteriorly, inferiorly and to the left side
atrium shifts posteriorly and superiorly
What will the truncus arteriosis form
roots and proximal portions of the aorta and pulmonary artery
What will the conus cordis form
outflow tracts of both ventricles
What will the primitive right ventricle form
trabeculated part of the right ventricle
What is dextrocardia
heart is on the right rather than the left
What is situs inversus
everything is flipped as well in the body
What will result from the incorporation of the right sinus horn into the right atrium
formation of IVC calve and coronary sinus valve
What is crest terminalis
dividing line between the trabeculated part of the right atrium and sinus venarum
What are endocardial cushions
thickenings of the sub-endocardium
What is the function of endocardial cushions
formation of atrial and ventricular walls, AV canals and valves, aortic and pulmonary channels
What is the role of endocardial cushions in the bulbous cordis
serve to partition the truncus
Where do endocardial cushions in the bulbous come from
neural crest cells
What is the role of endocardial cushions in the atria and ventricle
partition the atria, AV canals, and IV septum
Where do endocardial cushions in the atria and ventricle come from
not NCC
When will partitioning of the heart occur
day 27
Where are endocardial cushions derived from
mesoderm
What do endocardial cushions form in the atria
R and L atrioventricular canals
What are conotruncal ridges
ridges in region of the conus cordis and truncus arteriosus
What do conotruncal ridges do
separate the aorta and pulmonary trunk
Where do conotruncal ridges come from
NCC
What happens to the sinus venosum during week 5 of development
venous system remodels, shifts to right atrium
left horn regresses
What does the left horn of the sinus venosum develop into
coronary sinus and oblique vein of the LA
What does the right horn of the sinus venosum develop into
sinus venarum in wall of RA
What is the function of the coronary sinus
drain the heart
What are the 4 components of separation of the atria
septum primum
septum secundum
ostium primum
ostium secundum
What is the septum primum
descends towards endocardial cushions
What is the ostium primum
allows shunt of oxygenated blood from R to L
What is the ostium secundum
develops in septum primum
What is the septum secundum
to the right of the septum primum
What does the septum secundum create
foramen ovale
What is the function of the ostium primum
allows blood to bypass pulmonary circulation
