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Atlas of Human Embryos Chapter   Figure

C-6 neural arch, C-7 neural arch, C-7 spinal ganglion, anterior scalene muscle, body of sternum, brachial plexus, deltoid muscle, glenoid fossa, head of humerus, internal thoracic artery, jugular lymph sac, left brachiocephalic vein, left common carotid artery, left thymus (pouches 3 and 4), left vagus nerve (CN X), longus muscles, mammary gland primordium, middle scalene muscle, pectoralis major muscle, pectoralis minor muscle, phrenic nerve, rib 1, rib 2, rib 3, right brachiocephalic vein, right common carotid artery, right subclavian artery, right thymus (pouches 3 and 4), right vagus nerve (CN X), scapular notch, scapular spine, suprascapular nerve, supraspinatus muscle, sympathetic trunk, trachea, trapezius muscle, vertebral artery

A section through the sternum, viscera at the root of the neck and C-7 spinal ganglion.

Observe:
1. The bilateral thymus gland (pouches 3 and 4) deep to the sternum.
2. The brachiocephalic veins about to join to form the superior vena cava.
3. The bifurcation of the brachiocephalic artery next to the trachea into the right subclavian and right common carotid arteries.
4. The origin of the vertebral artery from the right subclavian artery ventral to which the right vagus nerve courses.
5. The left vagus nerve coursing between the left brachiocephalic vein and left common carotid artery.


Keywords: C-6 neural arch, C-7 neural arch, C-7 spinal ganglion, anterior scalene muscle, body of sternum, brachial plexus, deltoid muscle, glenoid fossa, head of humerus, internal thoracic artery, jugular lymph sac, left brachiocephalic vein, left common carotid artery, left thymus (pouches 3 and 4), left vagus nerve (CN X), longus muscles, mammary gland primordium, middle scalene muscle, pectoralis major muscle, pectoralis minor muscle, phrenic nerve, rib 1, rib 2, rib 3, right brachiocephalic vein, right common carotid artery, right subclavian artery, right thymus (pouches 3 and 4), right vagus nerve (CN X), scapular notch, scapular spine, suprascapular nerve, supraspinatus muscle, sympathetic trunk, trachea, trapezius muscle, vertebral artery

Source: Atlas of Human Embryos.