1. Peripheral Nervous system Nerves and neuronal cell bodies (ganglia) Nerves and neuronal cell bodies (ganglia)

2. Classification of Nerves Mixed nerves – both sensory and motor fibers Afferent (sensory) nerves – carry impulses toward the CNS Efferent (motor) nerves – carry impulses away from the CNS

3. Structure of nerve A bundle of neuron fibers found outside the CNS. A bundle of neuron fibers found outside the CNS. Endoneurium Endoneurium Perineurirm Perineurirm Epineurirm Epineurirm Mixed nerve: all spinal nerves are mixed nerves Mixed nerve: all spinal nerves are mixed nerves Afferent or sensory nerves Afferent or sensory nerves Efferent or motor nerves Efferent or motor nerves

5. Cranial Nerves 12 pairs of nerves that mostly serve the head and neck Numbered in order, front to back Numbered in order, front to back Three of cranial nerve are sensory. Three of cranial nerve are sensory.

6. Cranial nerves Olfactory … purely sensory (smell) Olfactory … purely sensory (smell) Optic…purely sensory ( vision) Optic…purely sensory ( vision) Oculomotor … motor fibers to muscles of the eye. Oculomotor … motor fibers to muscles of the eye. Trochlear ….motor to muscles of the eye. Trochlear ….motor to muscles of the eye. Trigeminal … sensory from the face and &motor to chewing muscles Trigeminal … sensory from the face and &motor to chewing muscles Abducens … motor to muscles of the eye. Abducens … motor to muscles of the eye.

8. Facial …m otor for face & sensory for taste Facial …m otor for face & sensory for taste Vestibulocohlear…sensory(balance & hearing) Vestibulocohlear…sensory(balance & hearing) Glossopharyngeal … motor fibers to pharynx & Glossopharyngeal … motor fibers to pharynx & sensory for taste

9. Vagus … sensory & motor for pharynx, larynx and viscera Vagus … sensory & motor for pharynx, larynx and viscera Accessory ….motor for neck and upper back. Accessory ….motor for neck and upper back. Hypoglossal … motor for tongue Hypoglossal … motor for tongue

11. Spinal nerves and nerve plexuses 31pairs of human spinal nerves 31pairs of human spinal nerves Spinal nerves are formed by combination of Ventral and dorsal roots Spinal nerves are formed by combination of Ventral and dorsal roots it divides into dorsal and ventral rami it divides into dorsal and ventral rami Both the spinal nerve and rami contain both motor and sensory Both the spinal nerve and rami contain both motor and sensory The smaller dorsal rami supply skin and muscles of posterior body trunk(muscles of back) The smaller dorsal rami supply skin and muscles of posterior body trunk(muscles of back)

14. The ventral rami of T1-T12 … intercostal nerves ….supply the muscles of anterior and lateral trunk The ventral rami of T1-T12 … intercostal nerves ….supply the muscles of anterior and lateral trunk Pleuxes :ventral rami of Pleuxes :ventral rami of cervical C1 to C5 cervical C1 to C5 brachial C5 to C8 &T1 brachial C5 to C8 &T1 lumbar L1 to L4 lumbar L1 to L4 sacral L4 &L5 and S1 to S4 sacral L4 &L5 and S1 to S4