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Atlas of Human Embryos Chapter   Figure

C-6 spinal ganglion, atrioventricular sulcus, axial artery, brachial plexus, dorsal primary ramus, dorsal root (sensory), edge of cerebral vesicle(s), endocardium, entrance of common pulmonary vein, epicardium, frontonasal area, heart prominence, interventricular septum (muscular portion), left atrium, left common cardinal vein, left primary bronchus, left ventricle, limb mesoderm, myocardium, pericardial cavity, phrenic nerve, placode, pleuropericardial fold, postcardinal vein, primitive lung sac, primitive meninx, primitive pleural cavity, right and left dorsal aortas, right atrium, right horn of sinus venosus, right pulmonary artery, right ventricle, sympathetic trunk, trabeculae carneae cordis, ventral primary ramus, ventral root (motor)

A section through the C-6 spinal ganglion and tracheal bifurcation forming primary bronchi.

Observe:
1. The brachial plexus surrounding the axial artery.
2. The pleuropericardial fold separating the primitive pleural and pericardial cavities.
3. The entrance of the common pulmonary vein into the left atrium.
4. The three layers of the heart wall: epicardium, myocardium and endocardium.
5. The trabeculae carneae cordis projecting into the ventricular chambers.


Keywords: C-6 spinal ganglion, atrioventricular sulcus, axial artery, brachial plexus, dorsal primary ramus, dorsal root (sensory), edge of cerebral vesicle(s), endocardium, entrance of common pulmonary vein, epicardium, frontonasal area, heart prominence, interventricular septum (muscular portion), left atrium, left common cardinal vein, left primary bronchus, left ventricle, limb mesoderm, myocardium, pericardial cavity, phrenic nerve, placode, pleuropericardial fold, postcardinal vein, primitive lung sac, primitive meninx, primitive pleural cavity, right and left dorsal aortas, right atrium, right horn of sinus venosus, right pulmonary artery, right ventricle, sympathetic trunk, trabeculae carneae cordis, ventral primary ramus, ventral root (motor)

Source: Atlas of Human Embryos.