Chapter 16-The Autonomic Nervous System

ACh is inactivated by what 2 things?

1. Acetylcholinesterase (AChE) 2. Tissue cholinesterase

What are the 2 types of sympathetic receptors?

1. Alpha receptors 2. Beta receptors

What 3 characteristics are shared by higher-order functions?

1. Are performed by neurons of the cerebral cortex and involve complex interactions between areas of the cortex and between the cerebral cortex and other parts of the brain. 2. Involve both conscious and unconscious information processing 3. Are subject to modification and adjustment over time.

Which 4 pairs of cranial nerves are associated with the cranial segment of the parasympathetic division of the ANS?

1. CN III (Oculomotor) 2. CN VII (Facial) 3. CN IX (Glossopharyngeal) 4. CN X (Vagus)

Which 6 plexuses in the thoracic and abdominopelvic cavities innervate visceral organs?

1. Cardiac plexus 2. Pulmonary plexus 3. Esophageal plexus 4. Celiac plexus 5. Inferior mesenteric plexus 6. Hypogastric plexus

What are the 6 effects of sympathetic versus parasympathetic stimulation in the thoracic and abdominopelvic cavities innervate visceral organs?

1. Cardiac- heart rate increases, force of heart contraction increases, blood pressure increases(sympathetic)/heart rate decreases, force of heart contraction decreases, blood pressure decreases(parasympathetic) 2. Pulmonary- Respiratory passageways dilate (sympathetic)/ Respiratory passageways constrict (parasympathetic) 3. Esophageal- Respiratory rate increases (Sympathetic)/ Respiratory rates decrease (parasympathetic) 4. Celiac- Digestion inhibited (sympathetic)/ Digestion stimulated (parasympathetic) 5. Inferior mesenteric- Digestion inhibited (sympathetic)/ Digestion stimulated (parasympathetic) 6. Hypogastric- Defecation inhibited, urination inhibited, & stimulate secretions in sexual organs (Sympathetic)/ Defecation stimulated, urination stimulated, & erection in sexual organs (parasympathetic)

What are the 3 types of ganglion?

1. Celiac ganglion 2. Superior mesenteric ganglion 3. Inferior mesenteric ganglion

Which three collateral ganglia serve as origins for ganglionic neurons that innervate organs or tissues in the abdominopelvic region?

1. Celiac ganglion 2. superior mesenteric ganglion 3. inferior mesenteric ganglion

Which 4 ganglia serve as origins for postganglionic fibers involved in control of visceral structures in the head?

1. Ciliary ganglion 2. pterygopalatine ganglion 3. Submandibular ganglion 4. Otic Ganglion

Higher order functions involve what 2 types of information processing?

1. Conscious 2. Unconscious

What are 2 other ways of saying deep sleep?

1. Non-REM sleep 2. Slow wave sleep

What are 5 age related changes in the nervous system?

1. Reduction in brain size and weight 2. A reduction in the number of neurons 3. A decrease in blood flow to the brain 4. Changes in the synaptic organization of the brain 5. Intracellular and extracellular changes in CNS neurons

What two distinctive results are produced by the stimulation of sympathetic ganglionic neurons?

1. Release of norepinephrine at specific locations 2. Secretion of epinephrine (and modest amounts of norepinephrine) into the bloodstream

Name 4 things that the autonomic nervous system affects?

1. Smooth muscle 2. glands 3. cardiac muscle 4. adipocytes

Integration of the SNS and ANS occurs at the level of what 2 things?

1. branstem 2. Higher centers

What are some general responses to increased parasympathetic activity?

1. decreased metabolic rate 2. decreased heart rate and blood pressure 3. Increased secretion by salivary and digestive glands 4, increased motility and blood flow in the digestive tract 5. Stimulation of urination and defecation

What are some general responses to increased sympathetic activity?

1. heightened mental alertness 2. increased metabolic rate 3. reduced digestive and urinary functions 4. activation of energy reserves 5. increased respiratory rate 6. dilation of respiratory passageways 7. Elevated heart rate and blood pressure 8. activation of sweat glands

What are some possible reasons for the slower recall and loss of memory that occur with age?

1. loss of neurons 2. changes in synaptic organization of the brain 3. Changes in the neurons themselves 3. Decreased blood flow which affects metabolic rate & slow retrieval of info from memory

What 3 things are included in higher-order functions?

1. memory 2. states of consciousness 3. neurotransmitters influence behavior

Postsynaptic membranes have what 2 types of ACh receptors?

1. muscarinic receptors 2. nicotinic receptors

What are the 2 types of cholinergic receptors on the postsynaptic membranes of parasympathetic neurons?

1. nicotinic receptors 2. Muscarinic receptors

What are the 2 distinctive results of the stimulation of the sympathetic division?

1. release of either ACh or norepinephrine (NE) at specific locations 2. the secretion of epinephrine (E) and norepinephrine (NE) into the general circulation

The nervous system also coordinates muscular activities associated with what 2 systems?

1. respiratory system 2. cardiovascular system

What are the 2 types of sympathetic ganglia?

1. sympathetic chain ganglia (paravertebral ganglia) 2. Collateral ganglia (preverebral ganglia)

How many motor neurons are needed to carry an action potential from the spinal cord to smooth muscles in the wall of the intestine?

2 neurons are needed to carry an action potential from the spinal cord to smooth muscles in the intestine. The 1st neuron carries the action potential from the spinal cord to the autonomic ganglion, and a 2nd neuron carries the action potential from the autonomic ganglion to the smooth muscles in the intestinal wall.

The sympathetic division includes how many _______ sympathetic chain ganglia, _______ collateral anglia, and ________ adrenal medullae.

2 sympathetic chain ganglia, 3 collateral ganglia, and two adrenal medullae

A typical preganglionic fiber synapses on how many ganglionic neurons?

6 to 8

Luke has a brain tumor that is interfering with the function of his hypothalamus. Explain why this tumor would interfere with autonomic function.

A brain tumor that interferes with hypothalamic function would also interfere with autonomic function, because centers in the hypothalamus are involved with autonomic (visceral) function

Damage to the hippocampus, a component of the limbic system, leads to what?

A loss of long-term memory

All parasympathetic preganglionic and post ganglionic fibers release what?

ACh

The neurotransmitter at all synapses and neuromuscular or neuroglandular junctions in the parasympathetic division of the ANS is _____?

Acetylcholine

What neurotransmitter is released by all parasympathetic neurons?

Acetylcholine (ACh)

When stimulated, sympathetic preganglionic neurons release what at synapses?

Acetylcholine (ACh)

All preganglionic autonomic fibers release__________ at their axon terminals, and the effects are always ______

Acetylcholine, excitatory

What produces various structural and functional changes in the nervous system?

Aging

What anatomical and functional changes in the brain are linked to alterations that occur with aging?

Aging causes a reduction in brain volume and weight, a reduction in the number of neurons, a decrease in blood flow to the brain, changes in synaptic organization, and intracellular and extracellular changes in the central nervous system neurons.

A progressive disorder characterized by the loss of higher-order cerebral functions is

Alzheimer's disease

What is the most common form of senile dementia?

Alzheimers disease

What is the loss of memory as a result of disease or trauma?

Amnesia

What physiological changes would you expect in a patient who is about to undergo a dental root canal and is quite anxious about the procedure?

An increase in sympathetic stimulation would result in dry mouth, increased heart rate, blood pressure, and rate of breathing, cold sweats, an urge to urinate or defecate, a change in the motility of the digestive tract (butterflies in the stomach), and dilated pupils

Where is the collateral ganglia located relative to the vertebral column?

Anterior to the vertebral column

What adjusts our basic life support systems without conscious control?

Autonomic nervous system

Why is the parasympathetic division sometimes referred to as the anabolic system?

Because parasympathetic stimulation leads to a general increase in the nutrient content of the blood. Cell throughout the body respond to the increase by absorbing the nutrients and using them to support growth and other anabolic activities

How would a drug that stimulates cholinergic receptors affect the sympathetic nervous system?

Because preganglionic fibers of the sympathetic nervous system release acetylcholine (ACh), a drug that stimulates cholinergic receptors would stimulate the postganglionic fibers of sympathetic nerves, resulting in increased sympathetic activity

A person with high blood pressure is given a medication that blocks beta receptors. How could this medication help correct that person's condition?

Blocking the beta receptors on cells would decrease or prevent sympathetic stimulation of tissues containing those cells. Heart rate, force of contraction of cardiac muscle, and contraction of smooth muscle in the walls of blood vessles would decrease, lowering blood pressure.

Which ganglion innervates the stomach, liver, gallbladder, pancreas, and spleen?

Celiac ganglion

Synapses that use ACh as a transmitter are called what?

Cholinergic

Nicotine stimulates cholinergic receptors of the ANS. Based on this info, how would cigarette smoking affect the cardiovascular system?

Cholinergic receptors are found in all the ganglia of the ANS, so nicotine would stimulate both sympathetic and parasympathetic responses in cardiovascular tissues. Although increased sympathetic stimulation increases heart rate and force of contraction, increase parasympathetic stimulation simultaneously decreases blood flow to the heart muscle. In addition to elevating heart rate and force of contraction, sympathetic stimulation also constricts peripheral blood vessels, all of which contribute to increase blood pressure

What type of ganglionic neuron innervates visceral organs in the abdominopelvic cavity?

Collateral ganglionic neurons

Under which of the following circumstances would the diameter of peripheral blood vessels be the greatest?

Decreased sympathetic stimulation

In what type of sleep does the body relax and cerebral activity is low?

Deep sleep or Non-REM sleep

What refers to the number of synapses a single preganglionic fiber may have with ganglionic neurons?

Divergence

What refers to situations in which vital organs & vital functions receive instructions from both sympathetic and parasympathetic fibers?

Dual innervation

You are home alone at night when you hear what sounds like breaking glass. What physiological effects would this experience probably produce, and what would be their cause?

Due to the stimulation of the sympathetic division, you would experience increased respiratory rate, increased peripheral vasoconstriction and elevation of blood pressure, increased heart rate and force of contraction, and an increased rate of glucose release into the bloodstream.

What physiological activities distinguish non-REM sleep from REM sleep?

During non-REM sleep, the entire body relaxes, and activity at the cerebral cortex is at a minimum; heart rate, blood pressure, respiratory rate, and energy utilization decrease. During REM sleep, active dreaming occurs, accompanied by alterations in blood pressure and respiratory rates; muscle tone decreases significantly, and response to outside stimuli decreases.

A (lower/higher) amount of divergence results in more complex and coordinated responses.

Higher

Why is autonomic tone a significant part of ANS function?

If autonomic motor neurons maintain a background level of activity at all times, they can either increase or decrease their activity, providing a greater range of control options.

What would happen if your RAS (Reticular Activating System) were suddenly stimulated while you were sleeping?

If your RAS were suddenly stimulated while you were asleep, it would rouse the cerebrum to a state of consciousness and you would wake up

Where do the nerves that synapse in collateral ganglia originate?

In the inferior thoracic and superior lumbar regions (between T1 & L2) of the spinal cord

The visceral reflex is an autonomic reflex initiated in what area of the body?

In the viscera

What cellular mechanisms identified in animal studies are thought to be involved in memory formation and storage?

Increased neurotransmitter release, facilitation of synapses, and the formation of additional synaptic connections are thought to be involved in memory formation and storage.

Effects produced by the parasympathetic branch of the Autonomic nervous system are what?

Increased secretion by digestive glands

What type of ganglion innervates the kidneys, urinary bladder, the terminal portions of the large intestine, and the sex organs?

Inferior mesenteric ganglion

Intramural ganglia typically consist of what?

Interconnected masses and clusters of ganglion cells

Where is the sympathetic chain ganglia located relative to the vertebral column?

It lies on each side of the vertebral column

What effect would the loss of sympathetic tone have on blood flow to a tissue?

It will relax the smooth muscles lining the vessels and it would increase blood flow to the tissues.

How would the stimulation of muscarinic receptors in cardiac muscle affect the heart?

It would cause K+ Channels to open, resulting in hyperpolarization of cardiac plasma membranes and a decreased heart rate.

What would be an effect of a drug that substantially increases the amount of serotonin released in the brain?

It would produce a heightened perception of certain sensory stimuli (EX auditory & visual) and hallucinations

In spinal segments T1 - L2, anterior roots give rise to the ___________ ______ ____ _____________, which in turn, leads to the _____________ __________ _________.

Myelinated white ramus communications; Sympathetic chain ganglia

Terminal ganglions are located where?

Near the target organ

Ganglionic neurons in ganglia are located where?

Near the vertebral column

What system controls the actions of the arrector pili muscles and sweat glands of the integumentary system?

Nervous system

What stimulates cholinergic receptors of the ANS?

Nicotine

What neurotransmitter is released from most varicosities in the sympathetic division?

Norepinephrine (NE) is released

terminal ganglia are usually______?

Paired

The effects produced by the (sympathetic/parasympathetic) division center on relaxation, food processing, and energy absorption.

Parasympathetic division

What type of reflexes govern respiration, cardiovascular functions, and other visceral activities?

Parasympathetic reflexes

Collateral ganglia is also called what?

Paravertebral ganglia

sympathetic chain ganglia is also called what?

Paravertebral ganglia

Preganglionis fibers leaving the sacral segments form what type of nerves?

Pelvic nerves

postganglionic fibers targeting structures in the body wall and limbs rejoin the spinal nerves and reach their destinations by way of what?

Posterior and anterior rami

What type of fibers targeting structures in the thoracic cavity form sympathetic nerves, which go directly to their visceral destinations?

Postganglionic fibers

What fibers form the sympathetic & parasympathetic division?

Preganglionic fibers

What type of fibers run between the sympathetic chain ganglia and interconnect them?

Preganglionic fibers

Starting in the spinal cord, trace an action potential through the sympathetic division of the ANS until it reaches a target organ in the abdominopelvic region.

Preganglionic neuron T5-L2---->collateral ganglia----->postganglionic fibers----->visceral effector in abdominopelvic cavity

In what type of sleep does active dreaming occur?

REM sleep

What is most important to arousal and the maintenance of consciousness?

Reticular Activating System (RAS)

What is the division of the nervous system that innervates skeletal muscles?

Somatic nervous system

During sympathetic stimulation, a person may begin to feel "on edge"; this is a result of what?

Stimulation of the reticular activating system

What type of ganglion innervates the small intestine and initial segments of the large intestine?

Superior mesenteric ganglion

The division of the ANS that prepares the body for activity and stress is the _________ division.

Sympathetic

In which division do axons emerge fro the thoracic and lumbar segments of the spinal cord and innervate ganglia relatively close to the spinal cord?

Sympathetic Division

In a crisis, the entire sympathetic division responds, ---an event call what?

Sympathetic activation

What division has a widespread influence on visceral and somatic structures?

Sympathetic division

What division is involved in using energy and increasing metabolic rate?

Sympathetic division

How does the emergence of sympathetic fibers from the spinal cord differ from the emergence of parasympathetic fibers?

Sympathetic preganglionic fibers emerge from the thoracolumbar areas (T1 through L2) of the spinal cord. Parasympathetic fibers emerge from the brain stem and the sacral region of the spinal cord (cranio-sacral)

As you recall facts while you take your A&P test, which type of memory are you using?

Test taking involves short-term memory

The short reflex bypasses what part of the nervous system?

The central nervous system

Why does sympathetic function remain intact even when the anterior roots of the cervical spinal nerves are damaged?

The preganglionic fibers innervating the cervical ganglia originate in the anterior roots of the thoracic segments, which are undamaged.

While out for a walk, Julie suddenly meets an angry dog. Which division of the autonomic nervous system is responsible for the physiological changes that occur in Julie as she turns and runs?

The sympathetic division of the ANS is responsible for the physiological changes that occur in response to stress (confronting an angry dog) and increased activity (running)

The condition known as shock is characterized in part by a decreased return of venous blood to the heart. How could an upsetting situation, such as the sight of a tragic accident or very bad news, produce some temporary symptoms of shock?

The upsetting situation would be processed by the higher centers of the central nervous system and relayed to the hypothalamus. The hypothalamus could suppress the vasomotor center of the medulla oblongata, resulting in fewer sympathetic impulses to peripheral blood vessels. This would cause a decrease in sympathetic tone int he smooth muscle of the blood vessels, resulting in vasodilation would cause blood to pool int he limbs, decreasing the amount of blood returning to the heart and producing shock.

Which nerve is responsible for the parasympathetic innervation of the lungs, heart, stomach, liver, pancreas, and parts of the small and large intestines?

The vagus nerve (X)

True or False: Higher order functions are subject to modification and adjustment over time.

True

What performs the simplest function of the ANS, and can be either long reflexes (with interneurons) or short reflexes (bypassing the CNS)?

Visceral reflex arcs

What are the components of a visceral reflex arc?

Visceral reflex arcs include a receptor, s sensory neuron, an interneuron (which may or may not be present), and two visceral motor neurons.

Special sensory inputs arrive by which cranial nerves?

Visual input arrives via CN II and auditory input arrives via VN VIII

What is a swollen segment that is packed with neurotransmitter vesicles?

a varicosity

ACh stands for ______?

acetylcholine

Neurons that release NE are called what?

adrenergic

Most postganglionic fibers are (Adrenergic/cholinergic/nitroxidergic); a few are (adrenergic/cholinergic/nitroxidergic)

adrenergic; cholinergic & nitroxidergic

What nervous system is involved in the unconscious regulation of visceral functions?

autonomic nervous system

Which nervous system coordinates cardiovascular, respiratory, digestive, urinary, and reproductive functions?

autonomic nervous system

The parasympathetic and sympathetic nerves intermingle in the thoracic and abdominopelvic cavities to form a series of what?

autonomic plexuses (nerve networks)

Even when stimuli are absent, autonomic motor neurons show a resting level of activation, the _____ _____.

autonomic tone

Changes in the normal ____________ between two or more neurotransmitters can profoundly affect brain function.

balance

The sympathetic division consists of preganglionic neurons located where?

between segments T1 & L2

Preganglionic neurons leaving the ________ & _________ segments form the parasympathetic division?

brain and sacral segments

The levels of activity in the sympathetic and parasympathetic divisions are controlled by

centers in the brainstem that regulate specific visceral functions

The abdominopelvic viscera receive sympathetic innervation by preganglionic fibers that synapse within which type of ganglia?

collateral ganglia

What are 2 other terms for the parasympathetic division?

craniosacral division & " rest and digest" system

The nervous system monitors all other systems and issues commands that adjust their activities. The efficiency of these activities typically (increases or decreases) with aging.

decreases

Intramural ganglions are located where?

embedded in the tissues of the target organ

(E) stands for ____?

epinephrine

The sympathetic division has a much (lower/higher) degree of divergence, where as then parasympathetic division has a much (lower/higher) degree of divergence.

higher; lower

Where do sympathetic ganglionic neurons end?

in telodendria studded with varicosities containing neurotransmitters

Specialized neurons are located where?

in the adrenal glands

A possible side effect of a drug used to open the airways of someone suffering from an asthma attack is ________?

increased blood pressure

The parasympathetic division has (short/long) preganglionis fibers and (short/long) postganglionic fibers.

long; short

Muscarinic receptors produce a (shorter/ longer) effect than does the stimulation of the nicotinic receptors.

longer

The conversion from short term to long term memory is called what?

memory consolidation

What is another word for autonomic plexus?

nerve networks

Different types of ______________________ & ____________________ lead to different sympathetic effects.

neurotransmitters and receptors

NE stands for ______?

norepinephrine

Where are beta receptors located?

on the plasma membranes of cells in many organs

The SNS and ANS are organized in (parallel/perpendicular)?

parallel

In which division do axons emerge from the brainstem and sacral segments of the spinal cord and innervate ganglia very close to target organs?

parasympathetic division

What division is involved in conserving energy and lowering metabolic rate?

parasympathetic division

Which division innervates areas serviced by cranial nerves and organs in the thoracic and abdominopelvic cavities?

parasympathetic division

The autonomic division of the nervous system directs

process that maintain homeostasis

What does REM sleep stand for?

rapid eye movement sleep

The sympathetic division has (short/long) preganglionic fibers and (short/long) postganglionic fibers?

short & long

The nervous system controls _____________ ________________ contractions of the muscular system, which in turn affects the (shrinking/thickening) of bones of the skeletal system?

skeletal muscle contractions; thickenings

The preganglionic fibers that innervate the collateral ganglia form what type of nerves?

splanchnic nerves

Amphetamines stimulate the secretion of which neurotransmitter?

stimulate the secretion of dopamine

What includes an increased alertness, a feeling of energy and euphoria, increased cardiovascular and respiratory activities, a general elevation in muscle tone, and a mobilization of energy reserves?

sympathetic activation

The autonomic nervous system is divided into what two divisions?

sympathetic and parasympathetic

What division is involved in using energy and increasing metabolic rate?

sympathetic division

Postganglionic fibers targeting structures in the thoracic cavity form what type of nerves?

sympathetic nerves

Preganglionic fibers enters an adrenal glad synapse within what?

the adrenal medulla

Higher order functions are performed by what?

the cerebral cortex

What is an autonomic motor response that can be modified, facilitated, or inhibited by higher centers, especially those of the hypothalamus?

the visceral reflex

Preganglionic neurons from the ________ & _________ segments form the sympathetic division?

thoracic and lumbar segments

What are 2 other terms for the sympathetic division?

thoracolumbar division & "flight or fight" system