Chapter 16 / Autonomic nervous system (A&PI)
The autonomic nervous system uses _____ to help maintain homeostasis in the absence of CNS input.
reflexes
Which are parasympathetic effects on the reproductive system?
-Stimulation of glandular secretion in the male reproductive tract -Penile or clitoral engorgement
How many neurons extend from the CNS to each effector tissue in the somatic nervous system?
1
How many neurons extend from the CNS to each effector tissue in the autonomic nervous system?
2
nerve plexus
A complex, interconnected neural network formed by neurons of the sympathetic and parasympathetic divisions
What is a preganglionic neuron?
A neuron that extends from the spinal cord or brainstem to a ganglion
Name the receptors that bind epinephrine and norepinephrine.
Adrenergic receptors
what is found in the sympathetic chain ganglion and in the collateral ganglion?
Cell bodies of postganglionic neurons of the sympathetic division
Name the location of the receptors for acetylcholine and norepinephrine.
Cell membrane
Which are parasympathetic effects on the urinary system?
Contraction of the urinary bladder wall Relaxation of the internal urethral sphincter
What are sympathetic effects on the digestive system?
Decreased pancreatic enzyme secretion Decreased pancreatic insulin secretion Decreased gastrointestinal secretion
What is the effect of parasympathetic stimulation on the heart?
Decreases heart rate
Which are associated with the parasympathetic division of the autonomic nervous system?
Defecation Digestion Urination
Name the effector site for the enteric nervous system (ENS)
Digestive tract
Identify the divisions of the Autonomic Nervous System (ANS). Select all that apply.
Enteric Nervous System Sympathetic Parasympathetic
Parasympathetic nerve signals will pass via the spinal nerves to reach the neck.
False
The autonomic nervous system regulates conscious, voluntary movements of skeletal muscles.
False
Name the sympathetic nerves or plexus whose axons innervate the salivary glands.
Head and neck nerve plexuses
Which are effects of the parasympathetic division on the digestive system?
Increased gastrointestinal secretion Increased gastric motility Increased pancreatic enzyme secretion
What is the effect of parasympathetic stimulation of muscarinic receptors in the stomach?
Increases muscle contraction
preganglia nuron
It has its cell body in the spinal cord or the brainstem and its axons terminates in the ganglion.
Describe the location of the ganglia of the parasympathetic nervous system.
Near or within the target organ
the location of the ganglia of the sympathetic nervous system.
Near the spinal column
Acetylcholine will bind to
Nicotinic and muscarinic receptors
Which part of the nervous system carries information to and from the CNS and various regions of the body?
Peripheral nervous system
Name the locations of the nicotinic receptors
Postganglionic neurons in the autonomic ganglia Skeletal muscle cells
Which are sympathetic effects on the urinary system?
Reduced urine output by the kidneys Contraction of the internal urethral sphincter
The peripheral nervous system (PNS) is composed of what types of neurons?
Sensory and motor nurons
Regarding the autonomic nervous system (ANS), identify the following relationships with sensory neurons
Sensory neurons can relay pain/pressure to the CNS from target organs. Sensory neurons can reflex-regulate organs. Sensory and ANS axons run in some of the same nerves.
Name the locations of the nicotinic receptors.
Skeletal muscle cells Postganglionic neurons in the autonomic ganglia
Which are sympathetic effects on the reproductive system?
Smooth muscle role in orgasm Labor contractions of the uterus
For the somatic motor nervous system,__________, Unavailable motor neurons carry impulses from the CNS to effectors (skeletal muscles). In the autonomic nervous system, ________, Unavailable (number) autonomic neurons carry signals from central nervous system to the effectors.
Somatic 2
Identify the nerves that transmit sympathetic information
Spinal nerves T1 - T12 Spinal nerves L1 - L2
adrenal medulla
The internal portion of the adrenal gland that secretes epinephrine and norepinephrine
What convention is used to name autonomic nerve plexuses?
They are named for the associated organs.
Describe a postganglionic neuron.
They are unmyelinated and extend from the autonomic ganglion to the target cells.
the parasympathetic nervous system has no effect on the breakdown fatty acids.
True
The somatic nervous system regulates conscious, voluntary movements of skeletal muscles. The ANS usually exhibits involuntary control.
Ture
The location of the cell body of a postganglionic neurons in the sympathetic division.
Within the sympathetic chain ganglion or within the collateral ganglion
The compound that binds to cholinergic receptors is ___
acetylcholine
Nicotinic and muscarinic receptors are receptors to which ____ will bind and alpha and beta receptors are receptors to which __ will bind.
acetylcholine epinephrine
Agonists bind to specific receptors and _____ them, whereas antagonists bind to specific receptors and _____ them
activate, inactivate
Agonists bind to specific receptors and _____ them, whereas antagonists bind to specific receptors and _____ them.
activate, inactivate
The inner region of the adrenal gland is the
adrenal medulla
If a sympathetic nerve secretes norepinephrine then the neuron is called a(n) _____ neuron.
adrenergic
Drugs that bind to specific receptors and activate them are called ______, whereas drugs that prevent activation are called ____
agonists, antagonists
Norepinephrine will bind to
alpha and beta receptors
The combined effects of the parasympathetic and sympathetic divisions on a target
are not always opposite in their effects
Homeostasis is maintained without CNS inputs by regulatory reflexes of the
autonomic nervous system
sympathetic NS is also described as "thoracolumbar"
because of the position of its preganglionic cell bodies
Autonomic nerve plexuses found supplying the heart___ and plexuses of the lunges are ________
cardiac plexuses Pulmonary plexuses
If a sympathetic nerve secretes acetylcholine, the neuron is called
cholinergic neuron
Identify the location of muscarinic receptors.
effector cells of postganglionic neurons
The division of the autonomic nervous system that is responsible for stimulating the secretion of glands used during digestion and the mixing of food contents is the
enteric nervous system
The rate of smooth muscle contraction in the digestive organs is increased when the neurotransmitters of the ______ division of the autonomic nervous system bind to _____ receptors.
enteric, adrenergic
All neurotransmitters result in excitatory stimulation when they bind to target receptors.
false
It is physiologically impossible for a target tissue to be stimulated by both the sympathetic and parasympathetic nervous systems.
false
The sympathetic division shunts blood and nutrients to structures that are active and away from non-essential organs. This is sometimes called the ____
fight-or-flight response
The primary function of the ANS is to
maintain homeostasis
Effector cells that respond to acetycholine released from postganglionic neurons possess ______ receptors on their cell membranes
muscarinic
Cholinergic receptors located in the membrane of all postganglionic neurons in the autonomic ganglia and in the membranes of skeletal muscle cells are
nicotinic or nicotine receptors
the craniosacral division is also known as the
parasympathetic nervous system.
A sudden increase in blood pressure initiates a ______ reflex that ______ the cardiac muscle cells.
parasympathetic, inhibits
Parasympathetic nerve signals will pass via the ______ to reach the large intestine.
pelvic splanchnic nerves
Preganglionic parasympathetic fibers from the sacral region of the spinal cord travel in
pelvic splanchnic nerves to reach the terminal ganglia.
In the sympathetic nervous system the preganglionic nerve fibers are ______ while the postganglionic fibers are ______
short, long
Depending on the body location, the parasympathetic division of autonomic nervous system is
stimulatory or inhibitory
Spinal nerves T1-L2 transmit information associated with the ___ division of the autonomic nervous system.
sympathetic
The increased breakdown of lipids within adipose tissue and thus the release of fatty acids may be induced by the ______ nervous system.
sympathetic
The autonomic nervous system is divided into the enteric nervous system, the ______ , Correct Unavailable division, and the ____ division.
sympathetic parasympathetic
The fight-or-flight response is associated with the
sympathetic division
The division of the autonomic nervous system that is more generalized and less localized is the
sympathetic nervous system
A sudden decrease in blood pressure initiates a _____ reflex that ______ the heart.
sympathetic/excites
Identify the functions of sensory neurons associated with the autonomic nervous system. Sensory neurons ___
transmit pressure sensations part of autonomic reflex arcs regulating organ activities transmit pain sensations