Chapter 17 Autonomic Nervous system
For the sympathetic nervous system, know the pathways traveled by the preganglionic and postganglionic fibers after leaving the spinal cord
-Preganglionic neurons in the lateral gray horns of spinal segments T1-L2. -Ganglia near the spinal cord - Preganglionic fibers release AcH stimulation ganglionic neurons. -Target organs - most postganglionic fibers release NE at neuroeffector junctions.
Describe the following features of the autonomic nervous system postganglionic neuron
Axon that leave the autonomic ganglia are relatively small and unmyelinated they are called postganglionic fibers because they carry impulses away from the ganglion. Postganglionic fibers innervate peripheral tissues and organs, such as cardiac and smooth muscle, adipose tissue and glands.
Describe the following features of the autonomic nervous system gray ramus
Postganglionic fibers that innervate structure in the body wall, such as the sweat glands of the skin or the smooth muscles in the superficial blood vessels, enter the gray ramus and return to the spinal nerve for subsequesnt distribution.
Describe the following features of the autonomic nervous system chain ganglia
Sympathetic chain ganglia help prepare the individual for a crisis that will require sudden, intensive physical activity. Visceral effectors in the thoracic cavity, head, body wall, and limbs.
Describe the pathways of preganglionic fibers in the parasympathetic nervous system.
The preganglionic fibers travel to the ciliary ganglion, pterygopalatine and submandibular ganglia, Otic ganglion, intramural ganglia, and Intramural/terminal ganglia then to target organs.
Know the differences in location, structure, and function between the parasympathetic and sympathetic nervous systems.
The sympathetic division of the ANS includes two sympathetic chains resembling string of beads, one on each side of the vertebral column three collateral ganglia anterior to the spinal column and two suprarenal medulla The parasympathetic division includes visceral motor nuclei in the the brainstem associated with four cranial nerves (III, VII, IX, X). In the sacral segments S2-S4 autonomic nuclei lie in the lateral portions of the anterior gray horns.
Describe the following features of the autonomic nervous system preganglionic neuron
Visceral motor neurons in the CNS, known as preganglionic neurons, send their axons called preganglionic fibers, to synapse on ganglionic neurons, whose cell bodies are located outside the CNS in the autonomic ganglia.
Compare the somatic and autonomic nervous systems
autonomic - Centers, nuclei, tracts, ganglia, and nerves involved in the unconscious regulation of visceral function; includes components of the CNS and PNS. Somatic - System of nerve fibers that run from the central nervous system to the muscles of the skeleton.
Describe the following features of the autonomic nervous system white ramus
carries myelinated preganglionic fibers into a nearby sympathetic chain ganglion,
What body structures are innervated by the autonomic nervous system
eye, salivary glands, Heart, lungs , liver and gallbladder, stomach, spleen, urinary bladder
What is a terminal ganglia?
ganglia found near the target organ.
Describe the following features of the autonomic nervous system collateral ganglia
postganglionic fibers that originate within the collateral ganglia extend throughout the abdominopelvic cavity, innervating visceral tissues and organ. Reduction of blood flow , energy use , and activity by visceral organs that nor important to short-term survival such as digestive tract and release of stored energy.
Describe the following features of the autonomic nervous system dual innervation
receiving instruction of both sympathetic and parasympathetic division.
Where are the postganglionic fibers of the parasympathetic nervous system located?
they are located in the terminal ganglia
Describe the following features of the autonomic nervous system sympathetic trunk
two long ganglionated nerve strands, one on each side of the vertebral column, extending from the base of the skull to the coccyx.
