Heart Development Flashcards
Pharyngeal arches contain
1.) Mesoderm
2.) Cartilage (to bone)
3.) Nerve
4.) Blood vessel
What is the purpose of heart development?
Creation of the mesoderm to primitive heart and vascular system
Establishment of vascular system
Timeline of heart development
1.) Primitive streak
2.) Mesodermal layer (trilaminar disc)
3.) Primary heart field (into lateral folds)
4.) 2 heart tubes
5.) Fused heart
6.) Formation of valves, etc.
During week _____, mesoderm and ________ ______ ___________ _____ travels through primitive streak toward the embryo’s _____ (day 16) and travel to the __________ mesoderm (which becomes the HEART)
3; primitive heart progenitor cells; head; splanchnic
During week 3, mesoderm also forms the _______ ________, these form in the cariogenic region and _____ to become a “horseshoe-shaped” mesoderm area with 2 limbs called the ________ ______ _____ or _______ _________ via vasculogenesis
Blood islands; fuse; Primary Cardiac Field or Cardiac Cresent
Vasculogenesis
form vessels that lead to two heart tubes aka the Secondary Cardiac Field
The RV (right ventricle) and outflow comes from the ______ cardiac crescent -> populates the pharynx before migrating to form the heart -> “_________ field” of cardiac precursor not part of early linear heart tube
medial; secondary
Week 3-4 (Day 19), _______ mesoderm splits into ________ and ________ layer
lateral; somatic and splanchnic
Week 3-4 (Day 19), when the body folds are growing ______ and fuse at the ventral midline the _________ - *VEGF signals to splanchnic mesoderm and thus the limb’s blood island cells to organize/specialize/differentiate into ___ endocardial tubes (mesoderm) AND pericardial cavities
laterally; Endoderm; 2
Week 3-4 (Day 21-22) Endoderm - VEGF influences _______ mesoderm and forms two ______ endocardial tubes
splanchnic; layered
2 layered endocardial tubes
1.) Angioblast
2.) Hemocytoblast
Angioblast
blood vessels -> heart tube -> endocardium
Hemocytoblast
blood cells
Week 3-4, concurrently, the embryonic coelom gives rise to ______ ________ ________ and forms ________ to each cardinal tube
primitive pericardial cavity; lateral
(week 3-4) Mesoderm cells also form a pair of longitudinal vessels called what?
Dorsal aorta
Layers of heart tube
1.) Endocardium
2.) Cardiac jelly secreted
3.) Myocardium
Heart develops ________ to _______
cranially; caudally
At first, the heart tube and pericardial coelom are ______, BUT when _____ folds, it pushes the heart (stuffs it) into the _________ cavity
separate; head; pericardial
- As the heart tube _____ the primordial myocardium forms from ________ mesoderm of the pericardial coelom
- The _______ (visceral pericardium) arise from the _____ surface of the _____ _______ and spreads on the myocardium
Fuse; splanchnic
Epicardium; external; sinus venosus
The heart tubes fuse into 1 and this tube will continue to __________
differentiate
Week 3, at ______ end, each endocardial tube connects to _________ ______ (x2) stemming from yolk sac
inferior; vitelline veins
Week 3/4, the embryo folds into a _________ shape as the lateral borders meet at ______ midline
cylindrical; ventral
(week 3-4) Two endocardial tube FUSE, becoming _______ ______ ____ with a single surrounding _________ ______
Left and right vitelline veins also FUSE to become _____ _______ (______ track)
Primitive Heart Tube; Pericardial Cavity
Sinus Venosus (inflow)
Ventral/visceral/splanchnic mesoderm becomes the _____
- it comes in contact with the endoderm
- there are inducible factors or signals VEGF between the endoderm and mesoderm and these form the heart, gut, etc.
heart