Heart Embryology Flashcards
What week does circulation begin during?
4th
What 3 things is the heart derived from?
- ) Splanchnic mesoderm
- ) Mesenchyme (neural crest)
- ) Angioblastic tissue
What layers do the heart fields develop between?
The endoderm and ectoderm
Where are the heart fields originally located? In what pattern?
The cranial end of the embryo in a horseshoe pattern
What layer are heart fields developed from?
Splanchnic mesoderm
Primary heart fields develop due to migration of what?
Mesoderm migrating during gastrulation
What does the primary heart field give rise to? (3 things)
- ) left atria
- ) right atria
- ) left ventricle
Secondary heart fields form from what? Where does this come from?
A second wave of mesoderm. Pharyngeal arches.
What does the secondary heart field develop into?
The right ventricle and outflow tract
The intraembryonic coelom gives rise to what?
The pericardial cavity
What is a mesentery?
A double layer of splanchnic mesoderm. It provides a route for blood vessels, nerves, and lymphatics to get to and from organs.
Is there a mesentery around the heart?
Yes
The heart is derived from what layer?
Splanchnic mesoderm
What are the three layers of the heart? What are they all derived from?
- ) Endocardium - internal epithelial layer
- ) Myocardium
- ) Epicardium (visceral pericardium)
Splanchnic mesoderm
When the dorsal mesocardium degenerates, what does it become?
The transverse pericardial sinus
What are 2 other names for heart fields?
- ) Cardiogenic cords
2. ) Heart tube
What is the dorsal mesocardium?
A mesentery that connects the heart fields
What does the newly formed transverse pericardial sinus separate?
The outflow tract from the venous flow
Where do the neural crest contributions of the heart originate?
The myelencephalon aka the medulla. So the brainstem
What pharyngeal arches do the NC cells that join up with the heart migrate through?
3, 4, and 6
Where do the NC cells end up?
The truncus arteriosus and the aorticopulmonary septa
What is the aorticopulmonary septa?
The septa that separates the aorta and the pulmonary trunk
What does too much vitamin a mess up? What can it cause?
Neural crest cell migration. It can cause cardiac defects
What genes regulate the migration of the cardiac NC cells?
Hox, NF-1, Pax 3
What are the primitive divisions of the endocardial heart tubes? (5 things)
- ) truncus arteriosus
- ) bulbus cordis
- ) Primitive ventricle
- ) Primitive atria
- ) Sinus venosus