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Chapter 15 : Autonomic Nervous System

Terms in this set (16)

Classify functions as somatic or autonomic
SOMATIC
- voluntary
- skeletal muscle activation
- principally involved with movement "of" the body
AUTONOMIC
- involuntary
- lacrimal gland activation
- intestinal smooth muscle activation
- principaly involced with movement of materials through the body
- sweat gland activation
- piloerector muscle activation
- can be excitatory or inhibitory on the target organ
Explaining the Function of Visceral Reflexes

- Primitive functions, such as blood pressure, heart rate, body temperature, metabolism, and respiratory airflow are regulated by the _____________.
- The ______________ system quietly manages a myriad of unconscious processes responsible for the body's homeostasis.
- This function is among the most ______________ of functions for animals to maintain healthy living conditions for life.
- Many drug therapies are based on the _____________ of autonomic functions.
- Primitive functions, such as blood pressure, heart rate, body temperature, metabolism, and respiratory airflow are regulated by the VISCERAL REFLEXES.
- The AUTONOMIC NERVOUS system quietly manages a myriad of unconscious processes responsible for the body's homeostasis.
- This function is among the most BASIC of functions for animals to maintain healthy living conditions for life.
- Many drug therapies are based on the ALTERATION of autonomic functions.
When body temperature increases, thermoreceptors are stimulated and send nerve signals to the CNS. The CNS sends motor signals to sweat glands, which attempt to reduce body temperature. This is an example of a _____________ reflex.
VISCERAL
A malfunctioning visceral reflex can be the cause of a(n) _____________, which can result in disorder and/or disease.
HOMEOSTATIC IMBALANCE
The _____________ division of the ANS increases alertness. The _____________ division has a calming effect on the body.
SYMPATHETIC; PARASYMPATHETIC
Explaining the Parasympathetic Pathway
*Then arrange the sentences into the order of occurrence of motor impulses in the ANS.
- Action potentials arriving at the sinoatrial and atrioventricular nodes of the heart cause _______________ to be released.
- Also known as the _______________ division, the parasympathetic nervous system has fibers exiting the CNS at the medulla oblongata.
- These impulses arrive at the cardiac plexus where secretion of acetylcholine creates an action potential in the _______________ neuron.
- Action potentials travel down the preganglionic nerve fibers of the _______________, towards the effectors organs.
- The parasympathetic neurotransmitter causes a _______________ in heart rate and contractility.
- The impulse arrives quickly at the heart, as parasympathetic postganglionic fibers are _______________ compared to sympathetic postganglionic fibers.
- Also known as the CRANIOSACRAL division, the parasympathetic nervous system has fibers exiting the CNS at the medulla oblongata.
- Action potentials travel down the preganglionic nerve fibers of the VAGUS NERVE towards the effectors organs.
- These impulses arrive at the cardiac plexus where secretion of acetylcholine creates an action potential in the POSTGANGLIONIC neuron.
- The impulse arrives quickly at the heart, as parasympathetic postganglionic fibers are SHORT compared to sympathetic postganglionic fibers.
- Action potentials arriving at the sinoatrial and atrioventricular nodes of the heart cause ACETYLCHOLINE to be released.
- The parasympathetic neurotransmitter causes a DECREASE in heart rate and contractility.
Explaining the Sympathetic Pathway
*Then arrange the sentences into the order of occurrence of motor impulses of the ANS.

- The effect of norepinephrine binding to ______________ receptors stimulates cardiac muscle cells.
- Action potentials travel along the preganglionic nerve fiber and enter the ______________.
- Also known as the ______________ division, the sympathetic nervous system exits the CNS via the spinal nerves from T1-L2.
- Arriving at target cells, ______________ nerve fibers release acetylcholine or norepinephrine into the synaptic cleft.
- Fibers exiting the sympathetic chain ganglia, take one of three routes: the spinal nerve route, the sympathetic nerve route, and the ______________ nerve route.
- Also known as the THORACOLUMBAR division, the sympathetic nervous system exits the CNS via the spinal nerves from T1-L2.
- Action potentials travel along the preganglionic nerve fiber and enter the SYMPATHETIC CHAIN GANGLION.
- Fibers exiting the sympathetic chain ganglia, take one of three routes: the spinal nerve route, the sympathetic nerve route, and the SPLANCHNIC nerve route.
- Arriving at target cells, POSTGANGLIONIC nerve fibers release acetylcholine or norepinephrine into the synaptic cleft.
- The effect of norepinephrine binding to ADRENERGIC receptors stimulates cardiac muscle cells.
The digestive tract has a nervous system of its own called the ______________ nervous system.
ENTERIC
Which of the following is/are functions of the enteric nervous system? Check all that apply.
◽️It regulates the movement of contents through the esophagus.
◽️It regulates the secretion of digestive enzymes.
◽️It innervates smooth muscles of the intestines.
◽️It innervates the sweat glands of the abdominal wall.
◽️It decreases using production.
☑️ It regulates the movement of contents through the esophagus.
☑️ It regulates the secretion of digestive enzymes.
☑️ It innervates smooth muscles of the intestines.
◽️It innervates the sweat glands of the abdominal wall.
◽️It decreases using production.
Describing Sympathetic and Vasomotor Tone
* Then place each sentence into a logical paragraph order

- An ______________ in firing rate constricts a vessel by increasing smooth muscle contraction.
- Thus, the sympathetic division alone exerts ______________ effects on the vessel.
- The sympathetic fibers to a blood vessel have a ______________ sympathetic tone.
- This tone keeps the vessels in a state of partial ______________, called vasomotor tone.
- A drop in firing ______________ a vessel by allowing the muscle to relax.
- The sympathetic fibers to a blood vessel have a BASELINE sympathetic tone.
- This tone keeps the vessels in a state of partial CONSTRICTION called vasomotor tone.
- An INCREASE in firing rate constricts a vessel by increasing smooth muscle contraction.
- A drop in firing DILATES a vessel by allowing the muscle to relax.
- Thus, the sympathetic division alone exerts OPPOSITE effects on the vessel.
Classifying the Physiological Effects of the ANS
SYMPATHETIC
- Releases norepinephrine to the heart
- Active during physical stress
- Increases the amount of air entering the alveoli of the lungs
- Maintains blood pressure
- Results in decreased urine production
PARASYMPATHETIC
- Associated with reduced energy expenditure
- Decreases the frequency of impulses initiated by the sinoatrial node of the heart
-Stimulates the smooth muscles of the digestive tract
Explaining Control Without Dual Innervation

- Many blood vessels only have innervation from the _______________ division of the ANS.
- To regulate blood pressure, the nerve fibers maintain a baseline degree of vessel constriction called _______________ tone.
- If there is a drop in blood pressure, the sympathetic neurons fire, increasing smooth muscle _______________ in the vessel.
- The diameter of the vessel _______________, which _______________ the pressure inside the vessel.
- Conversely, if there is an increase in blood pressure, a drop in sympathetic firing frequency will _______________ the smooth muscles and _______________ the lumen, decreasing pressure.
- Many blood vessels only have innervation from the SYMPATHETIC division of the ANS.
- To regulate blood pressure, the nerve fibers maintain a baseline degree of vessel constriction called VASOMOTOR tone.
- If there is a drop in blood pressure, the sympathetic neurons fire, increasing smooth muscle CONTRACTION in the vessel.
- The diameter of the vessel DECREASES, which INCREASES the pressure inside the vessel.
- Conversely, if there is an increase in blood pressure, a drop in sympathetic firing frequency will RELAX the smooth muscles and DILATE the lumen, decreasing pressure.
Clarifying ANS Receptors by Form and Function
ACETYLCHOLINE
- Muscarinic
- Nicotinic
- Associated with mushroom poison
- Associated with tobacco
- Only receptor found in parasympathetic synapses
NOREPINEPHRINE
- Alpha-Adrenergic
- Beta-Adrenergic
- Utilizes calcium ions as a second messenger
Clarifying Sympathetic and Parasympathetic Responses
SYMPATHETIC
- Increased heart rate
- Increased blood flow to skeletal muscle
- Reduced urinary output
- Increased pulmonary airflow
- Fight-or-Flight
PARASYMPATHETIC
- Activation of digestive organs
- Storage of energy
- Decreased pulmonary airflow
- Urinary bladder wall contraction
- Rest and Digest
Understanding Dual Innervation

- Dual innervation describes a scenario in which a target organ has innervation from ________________ division(s) of the ANS.
- If the divisions create opposite effects on the same organ, it's called ________________ innervation.
- If the divisions have complementary effects on the target organ or system, it's called ________________ innervation.
- Since the parasympathetic division causes the heart rate to ________________ and the sympathetic division causes the heart rate to ________________, this is an example of antagonistic innervation.
- Dual innervation describes a scenario in which a target organ has innervation from BOTH division(s) of the ANS.
- If the divisions create opposite effects on the same organ, it's called ANTAGONISTIC innervation.
- If the divisions have complementary effects on the target organ or system, it's called COOPERATIVE innervation.
- Since the parasympathetic division causes the heart rate to DECREASE and the sympathetic division causes the heart rate to INCREASE, this is an example of antagonistic innervation.
Classifying Central Control of Autonomic Function
CEREBRAL CORTEX
- Emotions can invoke autonomic responses
- Sexual thoughts or images can increase blood flow to the genitals
HYPOTHALAMUS
- It activates the fight-or-flight response
- It's the major control center of the ANS
- It's the integrating center for thermoregulation
BRAINSTEM
- It's the integrating centers for reflexes controlling bear rate and blood pressure
- It's the integrating center for the pupillary reflex
SPINAL CORD
- It's the integrating center for urination, defecation, erection, and ejaculation reflexes
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