A section through the T-6 spinal ganglion and caudal edge of the ventricles.
Observe:
1. The apex of the left ventricle and three layers of the heart wall.
2. The continuation of the left common cardinal vein in Section 32 with the left sinus horn (coronary sinus) that empties into the sinus venosus.
3. The pulmonary veins that course cranially from the lungs through the caudal part of the mesocardium in Section 32 before they empty into the left atrium.
4. The phrenic nerves in the pleuropericardial membrane dorsolateral to the heart.
5. The fissures that separate the lungs into lobes.
Keywords: T-6 spinal ganglion, anterior serratus muscle, apex of left ventricle, azygos vein, coronary sinus, edge of right atrium, endocardium, epicardium, erector spinae muscle group, interventricular sulcus, latissimus dorsi muscle, lower lobe, middle lobe, myocardium, oblique fissure, oblique sinus, phrenic nerve in pleuropericardial membrane, pleural cavity, right and left pulmonary veins, right venous valve, right ventricle, shaft of rib 6, sinus venosus, sternal bar, sympathetic trunk, transversospinal muscle group, upper lobe
Source: Atlas of Human Embryos.