Block 3_Chapter 16 Flashcards
The ________ division of the autonomic nervous system is said to function during “rest and digest.”
parasympathetic
The statement “its postganglionic axons always use acetylcholine as the neurotransmitter” is
True only to the parasympathetic nervous system
Which of the following would be an example of higher-level control of autonomic function?
increased heart rate when you see a person you fear
Muscarinic receptors
are normally activated by Ach
Alzheimer disease is characterized by all of the following, except that it
has a clear genetic basis
A decrease in the autonomic tone of the smooth muscle in a blood vessel would result in
both an increase in vessel diameter and an increase in blood flow through a vessel
In general, sympathetic preganglionic fibers are ________ and postganglionic fibers are ________.
both myelinated and short; unmyelinated and long
Sympathomimetic drugs might be used to
dilate airways
Which of the following is an example of a visceral reflex?
defacation reflex
vomiting reflex
pupillary reflex
ejaculation in response to tactile stimuli
Drugs that have effects similar to those of sympathetic activation are called sympathomimetic drugs. Which of the following would you not expect to observe in a person who has taken a sympathomimetic drug?
decreased blood pressure
Which of the following visceral reflexes is not coordinated by the medulla oblongata?
pupillary reflex
A state of unconsciousness in which an individual can be aroused by normal stimuli is
sleep
The suprarenal medullae (adrenal glands) secrete
both epinephrine and norepinephrine
Changes in the central nervous system that accompany aging include
- reduction in brain size and weight
- decrease in the number of neurons
- decreased blood flow to the brain
Ganglionic neurons innervate such things as
- smooth muscle
- cardiac muscle
- adipose tissue
- glands
An age-related decline in mental function characterized by difficulties with spatial orientation, memory, language, and personality is called
senile dementia
Sympathetic nerves
are bundles of postsynaptic fibers that innervate organs within the thoracic cavity
In the sympathetic nervous system, where are the preganglionic neurons located?
thoracic and lumber segments of the spinal cord
Drugs that block nicotinic receptors could
- suppress the transmission of nerve impulses in the autonomic nervous system
- suppress the generation of an action potential
- be classified as anti-cholinergic agents
- cause skeletal muscle paralysis
Dual innervation of an organ
implies that the organ is receiving input from both the parasympathetic and sympathetic nervous system
In general, autonomic tone of peripheral blood vessels increases when
sympathetic stimulation is increased
Nicotinic receptors
- open chemically gated sodium channels
- when activated cause a membrane depolarization
Stumulation of alpha 1 adrenergic receptors by NE results in
Release of Ca+ ions from intracellular stores
The statement “its ganglia are usually near or within the end organ” is
true only for the parasympathetic nervous system
Parasympathetic stimulation
increases gastric motility
Control of the diameter of the respiratory passages depends upon
both parasympathetic and sympathetic levels of stimulation
Mechanisms involved in memory formation and storage involve all of the following
- facilitation at synapses
- formation of additional synaptic connections
- the formation of memory engrams
- increase release of neurotransmitters
Parasympathetic blocking agents would be useful in treating
urinary incontinence (inability to control bladder muscle contractions)
Which of the following statements concerning the parasympathetic division of the autonomic nervous system is true
- the ganglionic neurons always release Ach
- preganglionic neurons are located in the brain stem and sacral region of the spinal cord
- ganglion neurons are located in ganglia within or near to effectors
- the actions of parasympathetic division are more localized than those of the sympathetic division
Depending on their location and function, postganglionic sympathetic axons can release which of the following neurotransmitters at their effector junctions?
- Ach
- NE
- nitric oxide
The conscious state is maintained by the
Reticular activating system (RAS)
An inhaler used to treat airway constriction in asthma or allergy might contain a drug that
Activates adrenergic receptors or blocks muscarinic cholinergic receptors
A neuron with nicotinic receptors is exposed to acetylcholine. This will lead to
activation of chemically gated ion channels, excitation of the neuron, and entry of sodium ion
Parasympathetic functions include all of the following
- stimulation of defecation
- stimulation of urination
- decrease in the rate of cardiac contraction
- constriction of the pupils
Preganglionic fibers leave the CNS and then synapse on
ganglionic neurons
In general, parasympathetic preganglionic fibers are ________ and postganglionic fibers are ________.
both myelinated and long; unmyelinated and short
Each of the following effects is associated with the action of postganglionic sympathetic fibers
- dilation of pupils
- reduced circulation to the skin
- increased sweat secretion
- increased blood flow to skeletal muscles
Which of the following is essential for memory consolidation
hippocampus
A certain drug decreases heart rate by blocking a receptor on cardiac pacemaker cells. This drug probably binds to ________ receptors.
beta-1 adrenergic
Postganglionic fibers release neurotransmitter on peripheral effectors
at pearl-like swellings called varicosities
Drugs known as beta-blockers may be useful for treating
excessive heart rate
Stimulation of the beta receptors on heart muscle cells results in
formation of cAMP, increased heart rate, increased force of contraction
The stimulation of beta-adrenergic receptors can lead to
- increase in metabolic activity
- inhibition of airway smooth muscle
- breakdown of triglycerides within adipocytes
After arousal by a sensory stimulus, consciousness can be maintained by positive feedback, because of activity in the
- cerebral cortex
- basal nuclei
- sensory pathways
- motor pathways
which of the following would lead to increased heart rate?
both increased sympathetic input and decreased sympathetic input
Autonomic tone is an important aspect of ANS function because it
allows ANS neurons to increase or decrease their activity, providing a range of control options
Activation of the sympathetic nervous system can lead to which of the following?
- elevated heart rate
- elevated blood pressure
- sweating
- elevated blood glucose
Most sympathetic effector junctions release norepinephrine but a significant number release acetylcholine instead. Which of these is an example of an organ of the cholinergic type?
a sweat gland (generalized)
The parasympathetic nervous system is especially active during which physiological state(s)
digestion
Drugs that stimulate alpha receptors, causing constriction of peripheral vessels, are
sympathomimetric
