Embryology - The Heart Flashcards
When does the vascular system appear?
Middle of third week
The progenitor heart cells lie immediately adjacent to the cranial end of the primitive streak. From there where do they migrate to?
They migrate through the primitive streak and into the splanchnic layer of lateral plate mesoderm.
Where does the primary heart field lie?
Cranial to the neural folds, into the splanchnic layer of lateral plate mesoderm.
What in the heart does the cells of the primary heart field form?
The atria, the left ventricle and part of the right ventricle
What in the heart does the cells of the secondary heart field form?
Part of the right ventricle and outflowtract (conus cordis and truncus arteriosus)
Where is the secondary heart field cells located?
It resides in splanchnic mesoderm, ventral to the pharynx.
Once the cells establish the primary heart field, they are induced by the underlying pharyngeal endoderm to do what?
To form cardiac myoblasts and blood islands that will form blood cells and vessels by the process of vasculogenesis.
Blood islands unite and form a horseshoe-shaped endothelial-lined tube surrounded by myoblasts. What is this region called?
The cardiogenic region.
The intraembryonic cavity over the cardiogenic region will develop to become?
The pericardial cavity.
In addition to the cardiogenic region, other blood islands appear bilaterally, parallel, and close to the midline of the embryonic shield. What will they form?
Those islands form a pair of longitudinal vessels, the dorsal aortae.
On which end is the heart tube elongated by cells form the secondary heart field?
Cranial end
DORV is a outflow tract defect. What is defect?
Both the aorta and pulmonary artery arise from the right ventricle.
Which day does the cardiac tube begin to bend?
Day 23
What is the space communicating between the common atria and the early embryonic ventricle called?
Atrioventricular canal
Which part of the bulbus cordis will form the trabeculated part of the right ventricle?
It’s proximal third
