Embryology Of Heart Flashcards
_____ is the 1st major system to develop
CVS
during the ____ week, a primordial uteroplacental circulation develops
3rd
____ week –angioblastic cords appear
Canalization of cords form ___________
2 tubes fuse to form ____ heart – _______ week
Heart beat begins –day __-___
3rd
endocardiac heart tubes
tubular; late 3rd
22-23
The endothelial heart tubes fuse to form a single _______ with a cranial (____) end and a caudal ( ______ ) end.
primitive heart tube
arterial
venous
As heart tube fuses, Surrounding mesenchyme ______ to form
•___cardium
•___cardium
➢ The two layers are separated by __________
thickens
Myo
Epi
cardiac jelly
__________ becomes endocardium
Endothelial tube
The primitive heart tube ______ and develops alternate ______ and _____ giving rise to an ___-shaped heart- the __-chambered heart
elongates
dilatations and constrictions
S
5
the 5-chambered heart •1- \_\_\_\_\_\_\_\_ •2-\_\_\_\_\_\_\_ •3-\_\_\_\_\_\_\_ •4-\_\_\_\_\_\_\_\_\_ •5-\_\_\_\_\_\_\_
truncus arteriosus.
bulbus cordis.
primitive ventricle.
primitive atrium.
sinus venosus.
The truncus arteriosus is continuous (cranially or causally?) with the _____, from which the _________ arise.
Cranially
aortic sac
pharyngeal arch arteries
The sinus venosus is continous (cranially or caudally?) and receives the
- ______ vein from the ____
- ______ vein from the ______
- ________ vein from the ____
Caudally
Umbilical; chorion
Vitelline; umbilical vesicle
Common cardinal; embryo
Bulboventricular loop
Because the ____ and ____ grow faster than other regions, the heart ___ upon itself, forming a ___-shaped bulboventricular loop.
As the primordial heart bends, the atrium and sinus venosus come to lie (ventral or dorsal?) to the TA, bulbus cordis, and ventricle
bulbus cordis
ventricle
bends
U
Dorsal
Partitioning of AV canal
•The junction between the ____ and _____ forms the AV canal
•Towards the end of 4th week, masses of tissue (_______) form on the _____ and ____ walls of the AV canal
•During the 5th week, the cushions _______ and _____, Partitioning the canal into ___ and _____
primitive atrium and ventricle
endocardial cushions
dorsal and ventral
approach each other and fuse
rt and lf AV canals
Partitioning of Primordial Atrium
•By the end of the 4th week, the primordial atrium is divided into ____ and ____ by 2 septa (______ and ____)
rt and lf atria
Primum and Secundum
Partitioning of atrium
- Septum primum- (thin or thick?) , _____ shaped membrane
- Grows from (roof or floor?) of _____ towards ________
- Leaves gap at its (upper or lower?) end- _____
- Atrium partially divided into Rt. & Lt. chambers & gap acts as a ____.
- As ostium primum becomes smaller, _____ appears at _____ part of the septum – ______
- Concurrently free edge of septum primum fuses with (right or left?) side of _____
Thin; cresentic
Roof; primordial atrium
fusing endocardiac heart cushion
Lower; ostium primum
shunt
Perforations; central
ostium secundum
Left
fused endocard. Cushion.
Septum secundum- A ____-shape, muscular membrane grow (upwards or downwards?) from ventrocranial (roof or floor?) of _____
To the (left or right?) side of _________
- ____week – overlaps foramen _____
- Forms incomplete partitioning- _____
cresentic
Downwards
Roof; rt atrium
Right; septum primum
5-6th
secundum
foramen ovale
Fate of Cranial portion of septum primum ???
Fate of Caudal part of septum primum becomes a ___ like valve of _____
It disappears
flap
foramen ovale