lecture 6 autonomics

Question 1

Sympathetics & Parasympathetics

fiber types and positions

Answer 1

Preganglionic fibers: thin myelin
Postganglionic fibers: unmyelinated
Sympathetic ganglia located near CNS
Parasympathetic ganglia near innervated organ

Question 2

Neurotransmitters types

Answer 2

All use Ach execpt for postganglionic in sympathetic system (norepinephrine)
Ach receptors are muscarinic (parasympathetic) and nicotinic in preganglionic sympathetic

Question 3

Sympathetic system

spinal cord levels and range

Answer 3

Preganglionic fibers from T1 to L2/3 segments

Travel in spinal nerve to sympathetic chain, prevertebral ganglia, adrenal gland

Question 4

Parasympathetic system

spinal cord levels and range

Answer 4

Preganglionic neurons located in brainstem & sacral cord
Travel in cranial & sacral nerves
Outflow to thoracic, abdominal and pelvic viscera; none to limbs

CNs 3,7,9, and 10 and sacral cord

Question 5

Cranial Nerve III - Oculomotor

Answer 5

Edinger-Westphal nucleus
Located in midbrain
Ciliary ganglion
Pupillary constrictor muscle fibers
Decreases pupil diameter (pupillary reflex)
Ciliary muscle
Accommodates lens for near vision

Question 6

Cranial Nerve VII - Facial

Answer 6

Superior salivatory nucleus in tegmentum of pons
Parasympathetic preganglionic cell bodies
Axons exit along with other facial nerve fibers
Terminate in:
Pterygopalatine ganglion
Location of postganglionic nerve cell bodies
Terminates in nasal and lacrimal glands
Submandibular ganglion
Location of postganglionic nerve cell bodies
Terminates in submandibular & sublingual salivary glands

Question 7

Cranial Nerve IX - Glossopharyngeal

Answer 7

Inferior salivatory nucleus - medulla
Parasympathetic preganglionic cell bodies of glossopharyngeal nerve
Axons exit along with other glossopharyngeal nerve fibers
Terminate in:
Otic ganglion
Location of postganglionic nerve cell bodies
Terminates in parotid salivary gland

Question 8

Cranial Nerve X - Vagus

Answer 8

Medulla:
Dorsal motor nucleus of the vagus
Parasympathetic preganglionic cell bodies serving GI tract and gut derivatives
Nucleus ambiguus
Parasympathetic preganglionic cell bodies serving heart
Axons exit along with other vagal nerve fibers
Terminate in:
Wall of target tissue
Viscera from thorax to transverse colon
Location of postganglionic nerve cell bodies