 Nerve :-A nerve is an enclosed, cable- like bundle of axons (the long, slender projections of neurons)  A cranial nerve nucleus:- is a collection head of neurons brain stem.  Ganglia :-mass of nerve cell bodies out of brain

 Sensory nerves are afferent nerves, they go to the brain. This makes sense because all the information from your senses are incoming to the brain. When you touch something hot neurons fire from the fingers to the brain. Motor nerves are efferent nerves which exit the brain. When you want to move an arm, axons fire from the brain to the arm.

 The nervous system is the part of an animal's body that coordinates the voluntary and involuntary actions of the animal

 Ⅰ Olfactory nerve  Ⅱ Optic nerve  Ⅲ Oculomotor nerve  Ⅳ Trochlear nerve  Ⅴ Trigeminal nerve  Ⅵ Abducent nerve  Ⅶ Facial nerve  Ⅷ Vestibulocochlear nerve  Ⅸ Glossopharyngeal nerve  Ⅹ Vagus nerve  Ⅺ Accessory nerve  Ⅻ Hypoglossal nerve

 Sensory cranial nerves : contain only afferent (sensory) fibers › Ⅰ Olfactory nerve › Ⅱ Optic nerve › Ⅷ Vestibulocochlear nerve  Motor cranial nerves : contain only efferent (motor) fibers › Ⅲ Oculomotor nerve › Ⅳ Trochlear nerve › Ⅵ Abducent nerve › Ⅺ Accessory nerv › Ⅻ Hypoglossal nerve  Mixed nerves : contain both sensory and motor fibers--- › Ⅴ Trigeminal nerve, › Ⅶ Facial nerve, › Ⅸ Glossopharyngeal nerve › Ⅹ Vagus nerve

Cranial Nerve I

 Component: Sensory  Function: Smell  Opening to the Skull: Openings in cribriform plate of ethmoid Origin: The olfactory mucosa of the upper part of the nasal cavity.

Cranial Nerve I: Olfactory

 Component: Sensory  Function: Vision  Opening to the Skull: Optic Canal  Origin: Back of the eyeball retina of the eye

 Component: Motor  Function:  Raises upper eyelid  Turns eyeball upward, downward and medially  Constricts pupil  Accommodates the eye  Opening to the Skull: Superior orbital fissure  Origin: Anterior surface of the midbrain

Component: Motor Function: Assisting in turning eyeball downward Opening to the Skull: Superior orbital fissure Origin: Posterior surface of the midbrain

Cranial Nerve V

V. Trigeminal Nerve

 Component: Sensory  Function:  Cornea  Skin of forehead  Scalp  Eyelids and nose  Mucous membranes of paranasal sinuses and nasal cavity  Opening to the Skull: Superior orbital fissure  Origin: Anterior aspect of the pons

Infratrochlear

V1. Ophthalmic Nerve

o Component: Sensory o Function: o Skin of the face over maxilla o Teeth of the upper jaw o Mucous membrane of the nose, the maxillary sinus and palate o Opening to the Skull: Foramen Rotundum o Origin: Anterior aspect of the pons

V2. Maxillary Nerve

o Component: a. Motor o Function: o Muscles of mastication o Mylohyoid o Anterior belly of digastric o Tensor veli palatine o Tensor tympani o Opening to the Skull: Foramen ovale o Origin: Anterior aspect of the pons

Component: b. Sensory Function: Skin of cheek Skin over mandible and side of head Teeth of lower jaw and TMJ Mucous membrane of mouth and anterior part of tongue Opening to the Skull: Foramen Rotundum Origin: Anterior aspect of the pons

V3. Mandibular Nerve

Component: Motor Function: Lateral rectus muscle turns eyeball laterally Opening to the Skull: Superior orbital fissure Origin: Medulla oblongata

VI. Abducent Nerve

 Component: Mixed  Function: Motor muscles of the face and scalp Stapedius muscle Posterior belly of digastric Stylohyoid muscles  Function: Sensory Taste from ant. 2/3 of tongue, from the floor of the mouth and palate

 Opening to the Skull: internal acoustic meatus, facial canal, stylomastoid foramen  Origin: Medulla oblongata  Function: Secretomotor Submandibular and sublingual salivary glands Lacrimal gland Glands of nose and palate

VII. Facial Nerve

o Component: Sensory o Function: o Vestibular - Saculae, saccule, semicircular canals – position of head o Cochlear – Organ of Corti - hearing o Opening to the Skull: Internal acoustic meatus o Origin: Medulla oblongata Two divisions – cochlear (hearing) and vestibular (balance)

VIII. Vestibulocochlear Nerve

Component: Mixed Function: Motor Stylopharyngeus muscle – assists swallowing Function: Sensory General sensation and taste from post. ½ of the tongue and pharynx Carotis sinus and carotid body Function: Secretomotor Parotid gland

Opening to the Skull: Jugular foramen Origin: Medulla oblongata

IX. Glossopharyngeal Nerve

Component: Motor Function: Heart and great thoracic blood vessels Larynx, trachea, bronchi and lungs Alimentary tract from pharynx to splenic flexure of colon Liver, kidney, pancreas Opening to the Skull: Jugular foramen Origin: Medulla oblongata The only cranial nerve that extends beyond the head and neck

X. Vagus Nerve

 Component: Motor  Function:  Cranial root  Muscles of soft palate (except tensor veli palatini)  Muscles pharynx (except styopharyngeus)  Muscles of larynx (except cricothyroid)  Spinal root  Sternocleidomastoid and trapezius muscle  Opening to the Skull: Jugular foramen  Origin: Cranial root medulla oblongata  spinal root : arising from the superior region of the spinal cord ( C1 – C6)  The spinal root passes upward into the cranium via the foramen magnum

 Component: Motor  Function: Muscles of tongue (except palatoglossus (cranial part of the accessory nerve) controlling its shape and movement)  Opening to the Skull: Hypoglossal canal  Origin: Medulla oblongata