Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
10 Cards in this Set
- Front
- Back
|
Describe the first step in the formation of the ventricles?
|
Median muscular ridge appears from the floor of the ventricle near its apex
Active proliferation of myoblasts allows for the formation of the muscular portion of the interventricular septum |
|
|
What is meant by the term Interventricular Septum?
|
In the 7th week the gap between the septum and endocardial cushions is closed forming the interventricular septum. This is accomplished by bulbar ridges.
|
|
|
What are the sources of closure of the IV foramen?
|
1)right bulbar ridge
2)left bulbar ridge 3)endocardial cushions 4)muscular IV septum |
|
|
Where does the membranous portion of the IV septum come from?
|
This is formed by an extension from the right side of the endocardial cushions
merges with: aorticopulmonary septum muscular portion IV septum |
|
|
Where do the bulbar ridges come from?
|
wall of bulbis cordis by proliferation of
mesenchymal cells neural crest cells 5th week |
|
|
Where does the aorticopulmonary septum arise from?
|
Formation of ridges causes fusion of bulbar and truncal ridges.
divides bulbis cordis and truncus arteriosus into two arterial channels aided by neural crest cells |
|
|
What are the adult remnants of the bulbis cordis?
|
Right Ventricle-conus arteriosus
left ventricle- aortic vestibule |
|
|
Which embryonic structure acts as the early pacemaker of the heart?
|
Sinus venosus
|
|
|
How is the SA node formed?
|
5th week
sinus venosus is incorporated into the wall of the right atrium |
|
|
How is the AV node formed?
|
When sinus venosus is incorporated into the atrium cells from the left wall are incorporated into the septum and along with cells from the AV region form the AV node and bundle.
|
