heart development Flashcards
(26 cards)
what does the intraembryonic cavity over the cardiogenic field later develop into?
pericardial cavity
the unit of blood islands that form a horseshoe shaped tube around the myoblasts is what?
cardiogenic field
what does the myocardium start to secrete only the heart tube is formed?
cardiac jelly
this separates the myocardium from the endothelium
what forms from the epicardium?
coronary arteries + endothelial lining
smooth muscle
what is the first bend the heart makes when forming the cardiac loop?
top portion bends ventrally, caudally, and to the right
the bottom portion shift dorsocranially and to the left
what will the proximal 1/3 of the bulbus cordis form?
trabeculated part of right ventricle
what will the conus cordis form?
outflow tracts of both ventricles
what will the truncus arteriosus form?
aorta and pulmonary artery
what does the primitive ventricle become?
the left ventricle
what is the master gene for heart development?
NKX2.5 (homologue of tinman)
what is an important gene for septation?
TBX5
looping requires which gene to be expressed on the left side of the heart in the lateral plate mesoderm?
PITX2
what is a common heart problem w/ Holt-Oram syndrome?
atrial and ventricular septal defects and conduction abnormalities
at the end of the shift of the sinus venosum of the heart, what is left of the left sinus horn?
oblique vein of the left atrium and coronary sinus
what happens to the right horn at the end of the development of the sinus venosus?
its incorporated into the right atrium to form the smooth walled part (sinus venarum)
What does the inferior portion of the right venous valve become?
valve of the IVC
valve of the coronary sinus
what are the masses of tissue called that grow until they fuse in the heart to form septa?
endocardial cushions
what is the sickle- shaped crest that grows from the roof of the common atria into the lumen?
septum primum (forms the opening= foramen primum)
what is the name of the perforations that develop in the upper part of the septum primum before it closes?
foramen secondum
A second septum grows down in the atrioventricular canal known as what and creates what?
septum secondum
creates the foramen ovale
what forms the smooth walled part of the left atrium?
pulmonary veins and their branches as they are incorporated into the left atrium
what are the original embryonic left and right atria represented by in the adult heart?
right and left auricle
what spiral swellings divide the truncus arteriosus into an aortic and pulmonary channel?
right superior truncus swelling
left inferior truncus swelling
what forms the muscular part of the interventricular septum?
the merging of the medial walls of the expanding ventricles becoming apposed
