Mastering A&P, Chapter 14, The Autonomic Nervous System
Define dual innervation.
-Dual innervation means that a given body system has twice the amount of neural stimulation needed to produce an action. -Dual innervation means that a given body system receives instructions from both the central and peripheral nervous systems. -Dual innervation means that a given body system receives instructions from both the sympathetic and parasympathetic divisions of the ANS. -Dual innervation means that sensory neurons and motor neurons are present in the tissue. -Dual innervation means that a given body system sends both sensory impulses and receives motor commands. Answer: Dual innervation means that a given body system receives instructions from both the sympathetic and parasympathetic divisions of the ANS.
What would happen to a cell exposed to the toxins in tobacco smoke if it had the right receptors to respond?
-It would activate or inactivate an enzyme. -It would decrease its activity. -Levels of cAMP would increase. -Ion channels would open. Answer: Ion channels would open.
Which of the following is a characteristic of the enteric nervous system?
-Many complex visceral reflexes of the ENS are initiated and coordinated through the CNS. -The ENS contains around one million neurons. -It is found in the walls of the heart. -All of the neurotransmitters found in the brain are found in the ENS Answer: All of the neurotransmitters found in the brain are found in the ENS
Which is correct regarding neurotransmitter release in the sympathetic division?
-Neurotransmitter release always involves muscarinic receptors. -Their receptors are located on the surfaces of all postganglionic cells and at neuromuscular junctions of the SNS. -Norepinephrine and epinephrine interact with adrenergic receptors in the plasma membrane. -It never involves activation of G proteins. Answer: Norepinephrine and epinephrine interact with adrenergic receptors in the plasma membrane.
Identify somatic effectors and visceral effectors.
-Somatic effectors are skeletal muscle, cardiac muscle, and smooth muscle. Visceral effectors are glands and adipose tissue. -Somatic effectors are smooth muscle, cardiac muscle, glands, and adipose tissue. Visceral effectors are skeletal muscle. -Somatic effectors are skeletal muscle. Visceral effectors are smooth muscle, cardiac muscle, glands, and adipose tissue. -Somatic effectors are glands and adipose tissue. Visceral effectors are skeletal muscle, cardiac muscle, and smooth muscle. -Somatic effectors are skeletal muscle, smooth muscle, cardiac muscle, and glands. Visceral effectors are adipose tissue. Answer: Somatic effectors are skeletal muscle. Visceral effectors are smooth muscle, cardiac muscle, glands, and adipose tissue.
Describe the ENS.
-The ENS is a division of the nervous system that includes the brain and spinal cord. -The ENS is a division of the nervous system that involves the voluntary movements of the skeletal muscle. -The ENS is a division of the nervous system consisting of a network of neurons and nerve networks in the walls of the digestive tract that primarily operates locally, without instructions from the CNS. -The ENS is a division of the nervous system that uses spinal reflexes to mediate changes in the effectors. -The ENS is a division of the nervous system that involves sensory input only. Answer: The ENS is a division of the nervous system consisting of a network of neurons and nerve networks in the walls of the digestive tract that primarily operates locally, without instructions from the CNS.
Which statement is true regarding the ANS?
-There is a single lower motor neuron in the autonomic centers of the ANS. -Ganglionic neurons in autonomic ganglia control skeletal muscles. -The integrative centers for autonomic activity are located in the hypothalamus. -The cell bodies of the upper motor neurons lie within the nuclei of the brain or at the primary motor cortex. Answer: The integrative centers for autonomic activity are located in the hypothalamus.
Neurons that use norepinephrine as a transmitter are called
-adrenergic. -muscarinic. -cholinergic. -nicotinic. Answer: adrenergic
Which of the following receptor types would respond most strongly to norepinephrine?
-alpha receptors -beta receptors -nicotinic receptors -muscarinic receptors Answer: alpha receptors
The sympathetic and parasympathetic divisions of the ANS:
-always have opposing effects. -cannot work independently. -never innervate the same organ. -may work together, each controlling a stage of a complex process. Answer: may work together, each controlling a stage of a complex process.
Autonomic motor neurons
-cause general relaxation. -conduct impulses to smooth and cardiac muscles and glands. -conduct impulses from sensory receptors. -conduct impulses to skeletal muscles. -cause general excitation. Answer: conduct impulses to smooth and cardiac muscles and glands.
Which of the following might result from activation of a beta receptor?
-increased heart rate -contraction of smooth muscle -initiation of an action potential -increased fat storage Answer: increased heart rate
Activation of the parasympathetic division of the ANS results in __________.
-increased motility and blood flow in the digestive tract -reduced digestive and urinary functions -increased metabolic rate -activation of sweat glands Answer: increased motility and blood flow in the digestive tract.
Specialized ganglionic sympathetic neurons that release hormones into the bloodstream are found within the
-intramural ganglia. -adrenal glands. -brainstem. -chain ganglia. -collateral ganglia. Answer: adrenal glands
Postganglionic sympathetic axons release the neurotransmitter ________ at their effector junctions.
-norepinephrine -acetylcholine or nitric oxide or norepinephrine -acetylcholine -nitric oxide -None of the answers is correct. Answer: acetylcholine or nitric oxide or norepinephrine
Activated nicotinic receptors __________.
-produce longer-lasting effects than other types of cholinergic receptors -open chemically-gated channels in the postsynaptic membrane -involve G proteins -are stimulated by muscarine Answer: open chemically-gated channels in the postsynaptic membrane.
The intrinsic eye muscles are the target organs of neurons from which parasympathetic ganglion?
-pterygopalatine ganglion -otic ganglion -ciliary ganglion -intramural ganglion (formed by pelvic nerves) Answer: ciliary ganglion
The sympathetic division of the ANS is also known as which of the following?
-resting division -craniosacral division -thoracolumbar division -somatic division -both somatic division and craniosacral division Answer: thoracolumbar division
Which of the following is an effect of sympathetic activation?
-stimulation of the medial and lateral pathways associated with a general elevation in muscle tone -change in blood flow and glandular activity associated with sexual arousal -constriction of the respiratory passageways -stimulation and coordination of defecation Answer: stimulation of the medial and lateral pathways associated with a general elevation on muscle tone
A visceral motor neuron whose cell body is within the CNS is called a(n) ________ neuron.
-upper motor -preganglionic -somatomotor -lower motor -postganglionic Answer: preganglionic
Which cranial nerve provides roughly 75 percent of all parasympathetic outflow?
CN III CN VII CN X CN IX Answer: CN X