The ductus venousus is closed, forcing blood from the hepatic portal system into general venous circulation and thus forces the use of what organ?
Liver
Vessels form from splanchnopleuric mesoderm of the yolk sac aggregate to form...
Blood islands
annulus fibrosis
Where do myofilaments develop?
cytoplasm of myotubes
What process causes cartilaginous precursors of the limb bones to develop
chondrofication
The trachea and bronchi are derived from the growth and division of the...
lung bud
Where does heart fusion begin?
cranial end
Bone develops from either ____ or ____.
mesenchyme or cartilage
perimysium and epimysium
What do bone and blood vessels of the limb arise from?
lateral plate mesoderm of the limb buds
After the first breath, umbilical circulation stops. What closes then to force blood into the pulmonary circuit?
ductus arteriosus
Describe the three classifications of embryonic veins
Vitelline, umbilical, common cardinal
The base of the occipital bone is derived from what sclerotome?
C1
Describe what happens in the hyperblastic phase of muscle development.
increase in muscle cell number
What forms the apical ectodermal ridge?
ectoderm on distal margins
What are the lung maturation stages? (4)
Pseudoglandular, Canalicular, Terminal sac, Alveolar
Closure of the Membranous IV results in...
separation of pulmonary and systemic circuits
In the formation of the vertebral column, each vertebra is derived from caudal portion of the corresponding sclerotome above and the cranial portion of the corresponding sclerotome below. Describe the cell composition difference between the caudal portion and cranial portion
Caudal- densely packed cells
Cranial- loosely packed cells
What does cardiac muscle develop from? What do the myoblast then differentiate to form?
Splanchnic mesenchyme surrounding the heart
primordial myocardium
During limb development, growth is stimulated in what direction?
proximodistal direction
The diaphragm is derived from what 4 tissues?
septum transversum
pleuroperitoneal membrane
paraxial mesoderm of the body wall
esophageal mesoderm
Through the 5th to 8th week the heart tube elongates with looping and remodeling into 4 chambers. Name the 4 chambers.
Inflow area, primitive atrium, primitive ventricle, bulbous cordis
During the mesenchymal stage, the mesenchymal cells from the sclerotomes are found in what 3 areas?
around notochord
surrounding neural tube
in the body wall
It was once thought that innervation would determine whether a muscle would become a slow or fast twitch fiber. However, molecular studies indicated that differentiation of what occurred before motor axon invasion?
primary myotubules
A muscle formed becomes an adductor of the lower extremity. What likely innervates this muscle?
(Dorsal or ventral primary rami?)
ventral primary rami