Biol 231 Peripheral Nervous System + Autonomic Nervous System

How many pairs of cervical nerves are there?

eight

How many pairs of thoracic nerves are there?

twelve

How many pairs of lumbar nerves are there?

five

How many pairs of sacral nerves are there?

five

How many pairs of coccygeal nerves are there?

one

spinal nerve structure

attaches to the spinal cord by a ventral (anterior) root + a dorsal (posterior) root

dorsal root ganglion

swelling in the dorsal root of each spinal nerve

ramus

the large branching of spinal nerves

plexuses

branching to innervate particular parts of the body

dermatomes

afferent (sensory) neurons of spinal nerves supplying the skin

myotomes

efferent (motor) neurons of spinal nerves supplying skeletal muscles

cranial nerves

twelve pairs of cranial nerves connect to the brain, mostly the brainstem

olfactory nerve (I)

smell

optic nerve (II)

sight

trochlear (IV) and abducens (VI) nerves

eye muscles

oculomotor nerve (III)

eye muscle

trigeminal muscle (V)

mastication

facial nerve (VII)

salivatory glands, taste buds

vestibulocochlear nerve (VIII)

hearing

glossopharyngeal nerve (IX)

tongue, pharynx, carotid sinus

vagus (X) and accessory (XI) nerves

respiratory, digestive

hypoglossal nerve (XII)

tongue

somatic nervous system

afferent (sensory) and efferent (motor) divisions

efferent somatic nervous system

somatic motor nervous system and efferent portion of the autonomic nervous system

somatic reflexes

response to a stimulus

autonomic nervous system

afferent (sensory) and efferent (motor) components, regulating heartbeat, smooth muscle, glandular secretions, and metabolism (maintains homeostasis)

autonomic nervous system divisions

parasympathetic and sympathetic divisions

sympathetic division

controls “fight or flight” reaction, increased heart rate, respiration, and metabolism, sends energy to skeletal muscles

parasympathetic division

“rest and repair” reaction, decreased heart rate, respiration, and metabolism, energy to “normal” visceral function