Flashcards in Heart Development - WTF Deck (67)
Before birth, how is blood shunted?
From right to left atrium
When does heart formation begin and when does heart start beating?
Initial function of heart
One way pump to transport O2 blood from placenta to the embryo
Umbilical vein function
Carries blood from placenta to embryo
Umbilical arteries functionm
Carry blood from embryo to placenta
Cardiogenic region...where is it and what happens?
At the rostral end...mesodermal cells aggregate to form longitudinal cellular strands (angioblastic cords)
What germ layer is the majority of the heart composed from?
How is primitive heart tube formed?
Angioblastic cords hollow out to form endocardial heart tubes
What does longitudinal folding accomplish for the heart?
Positions it in the thorax
Embryonic folding brings
Two endocardial tubes into the thorax where they meet along midline and fuse to form a single tube
Fused endocardial tubes form the ______
Inner lining of the heart
What happens to mesoderm below pericardial coelom as heart tube fuses?
Forms cardiac jelly and myocardium
Pericardial coelom is the future _______
Thick, inner gelatinous mix
Parietal pericardium is from ______ mesoderm
Visceral pericardium from ______ mesoderm
Dorsal mesocardium does what and then leaves what remnant?
Anchors heart at the beginning and goes away to form transverse pericardial sinus
Flow through the parts of pirmitive heart tube
Sinus venosus------atrium-----ventricle------bulbis cordis--------truncus arteriosis---------aortic arch vessels
These are caudal to rostral
Pericardial sac from what parts of the primitive heart tube?
Truncus arteriosis becomes
How does sinus venosus receive blood
Common cardinal veins (body)
Umbilical veins (placenta)
Vitelline veins (yolk sac)
Blood flows from the aortic arches into the _________ to reach the body, placenta, and yolk sac
Heart abnormally positioned on the right side of the thorax
Dextrocardia with situs inversus
No cardiac abnormality because inversion of all organs
Four sets of partitions of primitive heart
Atria and ventricles
R and L atria
R and L ventricle
Pulmonary trunk and ascending aorta
Atrioventricular canal and what develops there during week 4
Between pirmitive atrium and ventricle
Endocardial cushions grow together to create
Septum primum grows how?
From roof of atrium and extends toward endocardial cushions