chapter 6.18 EXAM 2 Flashcards
what are the functional divisions of the autonomic nervous system?
the sympathetic and parasympathetic divisions.
What are the two types of neurons in the sympathetic division?
postganglionic neuron and preganglionic neuron.
Describe the preganglionic neurons in the sympathetic division.
originate in the thoracolumbar spinal cord.
short fibers that immediately synapse at a ganglion upon exiting the spinal cord.
sympathetic chain ganglia.
collateral ganglia
what are sympathetic chain ganglion?
collections of ganglia that are located lateral to the vertebral column.
What are collateral ganglia?
ganglia that are located roughly half-way to the effector organ.
Describe the postganglionic neurons in the sympathetic division.
continue from the ganglion to the effector organ.
much longer than the preganglionic fibers.
usually terminate in varicosities.
What are varicosities?
knob-like structures that allow for release of neurotransmitters over a larger area.
What do varicosities and gap junctions allow for?
the neurotransmitter to effect the whole organ and not just one cell.
What is the adrenal medulla considered?
a modified sympathetic ganglion.
Describe the preganglionic neurons in the parasympathetic division.
originate in the brain, brainstem, or sacral spinal cord.
axons travel toward the effector organ where they synapse at a terminal ganglion, adjacent to the effector organ.
Describe the postganglionic neurons in the parasympathetic division.
fibers are short and terminate on the effector organ.
usually terminate in varicosities.
Describe the heart in the sympathetic division.
increase in rate of contraction and force of contraction.
Describe the blood vessels in the sympathetic division.
blood vessels to the digestive organs and skin are constricted.
blood vessels to the skeletal muscles and heart are dilated.
Describe the lungs in the sympathetic division.
bronchioles are dilated
mucus secreation is inhibited
Describe the eye in the sympathetic division.
pupil is dilated
lens is set for far vision
Describe the gall and urinary bladder in the sympathetic division.
both are relaxed.
Describe the digestive system in the sympathetic division.
decreased motility, sphincters contracted, decreased enzyme secretions.
Describe the liver in the sympathetic division.
glycogenolysis (glucose is released).
Describe fat in the sympathetic division.
release of fatty acids.
Describe the endocrine glands in the sympathetic division.
sweat glands increase sweat production.
exocrine pancreas decreases secretion
salivary glands increase mucus production in saliva, but decreased volume of saliva.
Describe the brain in the sympathetic division.
increase in alertness
Describe the genitalia in the sympathetic division.
ejaculation and orgasmic contractions.
Describe the heart in the parasympathetic division.
decreased heart rate, decreased force of atrial contraction.
Describe the blood vessels in the parasympathetic division.
the only blood vessels that are innervated by parasympathetic fibers are associated with the genitalia and these will be dilated.
Describe the lungs in the parasympathetic division.
bronchioles are constricted.
mucus secretion is stimulated.
Describe the digestive tract in the parasympathetic division.
increased motility, relaxation of sphincters, stimulation of digestive secretions.
Describe the gall and urinary bladders in the parasympathetic division.
emptying
Describe the eye in the parasympathetic division.
pupil is constricted.
lens is accomodated for near vision.
Describe the exocrine glands in the parasympathetic division.
exocrine pancreas releases digestive enzymes.
salivary glands release large volumes of water saliva with amylase.
Describe the genitaia in the parasympathetic division.
erection.
What are the three exceptions to the dual innervation rule?
- blood vessels
- sweat glands
- salivary glands
Describe blood vessels and the dual innervation rule.
exception.
blood vessels are only altered in the sympathetic division.
however, blood vessels to the erectile tissue of the penis and clitoris receive sympathetic and parasympathetic.