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Atlas of Human Embryos Chapter   Figure

T-2 intercostal nerve, T-2 spinal ganglion, aorta, aortic semilunar valve, diaphragm, ductus arteriosus, erector spinae muscle group, infraspinatus muscle, interventricular septum, interventricular sulcus, intrapulmonary bronchus, left atrium (primitive part), left coronary artery, left phrenic nerve, left pulmonary artery, left ventricle, liver, middle lobe of right lung, rib 2, rib 5, rib 7 (costal cartilage), right atrium (primitive part), right atrium (sinus venosus part), right pulmonary artery, right venous valve, right ventricular chamber, scapula, subscapularis muscle, tracheal bifurcation, transversospinal muscle group, tranverse process of T-2 vertebrae, upper lobe of left lung, upper lobe of right lung, vagus nerve (CN X)

A section through the cranial edge of the liver and diaphragm, tracheal bifurcation and T-2 spinal ganglion.

Observe:
1. The interventricular septum separating the right and left ventricular chambers.
2. The aortic semilunar valve between the left atrium and ascending aorta where the coronary arteries arise.
3. The junction of the superior vena cava in Section 18 with the sinous venosus part of the right atrium.
4. The bifurcation of the pulmonary trunk into right and left pulmonary arteries.
5. The ductus arteriosus connecting the pulmonary trunk with the aorta.


Keywords: T-2 intercostal nerve, T-2 spinal ganglion, aorta, aortic semilunar valve, diaphragm, ductus arteriosus, erector spinae muscle group, infraspinatus muscle, interventricular septum, interventricular sulcus, intrapulmonary bronchus, left atrium (primitive part), left coronary artery, left phrenic nerve, left pulmonary artery, left ventricle, liver, middle lobe of right lung, rib 2, rib 5, rib 7 (costal cartilage), right atrium (primitive part), right atrium (sinus venosus part), right pulmonary artery, right venous valve, right ventricular chamber, scapula, subscapularis muscle, tracheal bifurcation, transversospinal muscle group, tranverse process of T-2 vertebrae, upper lobe of left lung, upper lobe of right lung, vagus nerve (CN X)

Source: Atlas of Human Embryos.