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Atlas of Human Embryos Chapter   Figure

C-4 spinal ganglion, C-4 spinal nerve, C-5 spinal ganglion, bifurcation of common carotid artery, branchial groove, cerebral prominence, cerebral vessels, cheek, conjunctiva, cornea, dorsal primary ramus, dorsal root (sensory), external jugular vein, facial nerve branches, hypoglossal nerve (CN XII), internal jugular vein, interventricular foramen, jugular lymph sac, lamina terminalis, laryngeal cartilages, lateral palatine process, lens, longus muscles, mandibular lamina, mantle layer, marginal zone, maxillary labiodental lamina, origin of nasolacrimal duct, oronasal membrane, pharyngeal arch 1 cartilage (Meckel), primitive nasal cavity, primitive oral cavity, primordial gyrus dentatus, primordial tuberculum olfactorium, primordial vitreous body, tongue, trabecular cartilage (nasal septum), ventral primary ramus, ventral root (motor)

A section through the laryngeal cartilages and caudal part of the primitive nasal cavity.

Observe:
1. The oronasal membrane separating the primitive oral and nasal cavities.
2. The mandibular lamina located superficial to the terminal branches of the facial nerve.
3. The hypoglossal nerve coursing into the tongue.
4. The bifurcation of the common carotid artery.
5. The roots and primary rami of a spinal nerve.


Keywords: C-4 spinal ganglion, C-4 spinal nerve, C-5 spinal ganglion, bifurcation of common carotid artery, branchial groove, cerebral prominence, cerebral vessels, cheek, conjunctiva, cornea, dorsal primary ramus, dorsal root (sensory), external jugular vein, facial nerve branches, hypoglossal nerve (CN XII), internal jugular vein, interventricular foramen, jugular lymph sac, lamina terminalis, laryngeal cartilages, lateral palatine process, lens, longus muscles, mandibular lamina, mantle layer, marginal zone, maxillary labiodental lamina, origin of nasolacrimal duct, oronasal membrane, pharyngeal arch 1 cartilage (Meckel), primitive nasal cavity, primitive oral cavity, primordial gyrus dentatus, primordial tuberculum olfactorium, primordial vitreous body, tongue, trabecular cartilage (nasal septum), ventral primary ramus, ventral root (motor)

Source: Atlas of Human Embryos.