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Atlas of Human Embryos Chapter   Figure
 <   >  search results: primordial endocardium Search   Fig. 4-5-6 Fig. 4-6-7 Fig. 4-7-9

caudal edge of somite 1 (O-1), cut edge of amnion, edge of sinus venosus, endoderm, endomyocardial space, foregut, intermediate mesenchyme, lateral mesoderm, left dorsal aorta, neural canal, neural tube, paraxial mesoderm, pericardial cavity, primary head vein, primitive left atrium, primitive right atrium, primordial endocardium, primordial epimyocardium, septum transversum, somatic mesoderm, splanchnic mesoderm, unpaired lung primordium

A section through the caudal part of somite 1 and the pericardial cavity at the level of the lung primordium.

Observe:
1. The reduction in the size of the endomyocardial space.
2. The cranial edge of the left sinus venosus where it becomes continuous with the primitive left atrium.
3. The close relation of the unpaired lung primordium to the heart.
4. The division of mesoderm into paraxial (somitic), intermediate and lateral portions.
5. The subdivision of lateral mesoderm into splanchnic and somatic portions.


Keywords: caudal edge of somite 1 (O-1), cut edge of amnion, edge of sinus venosus, endoderm, endomyocardial space, foregut, intermediate mesenchyme, lateral mesoderm, left dorsal aorta, neural canal, neural tube, paraxial mesoderm, pericardial cavity, primary head vein, primitive left atrium, primitive right atrium, primordial endocardium, primordial epimyocardium, septum transversum, somatic mesoderm, splanchnic mesoderm, unpaired lung primordium

Source: Atlas of Human Embryos.