Chapter 12, 15, 11, 13, 14 and 16
True or false: Unmyelinated nerve fibers (axons) in the PNS are enveloped in Schwann cells.
TRUE Reason: Although the Schwann cell's plasma membrane does not spiral repeatedly around the axon as it does when forming a myelin sheath, it does fold once around each axon to form the neurilemma.
What are the parasympathetic functions of the oculomotor nerve?
To adjust the shape of the lens and the diameter of the pupil
What is the primary function of the myelin sheath?
To increase the speed of signal conduction in the axon
In the spinoreticular tract, the second order neurons decussate to where?
Contralateral anterolateral system
Which is true about a neuron with a large diameter, myelinated axon as compared to a neuron with a small diameter, unmyelinated axon?
Signal conduction will be faster
Which ganglia extend from the cervical region to the coccygeal region along the vertebral column?
Sympathetic chain
Where are free nerve endings most abundant?
Skin and mucous membranes
Why is sodium more concentrated in the ECF than in the ICF of most neurons?
Sodium is actively pumped out of the cell by transporter proteins.
Which nervous system transmits only excitatory signals to effector cells?
Somatic nervous system
Signals for proprioception are carried by the anterior and posterior ___________ tract
Spinocerebellar
Select all that apply What are the characteristics of a phasic receptor? Select all that apply.
adapts quickly to a stimulus produces a quick burst of action potentials
Select all that apply What are the characteristics of a tonic receptor? Select all that apply.
adapts slowly to stimulus produces a steady, prolonged response
The adrenal gland has two parts, an outer rim called the _________ ________ and an inner portion called the ____________ ___________
adrenal cortex adrenal medulla
Which portion of the adrenal gland secretes epinephrine, norepinephrine, and a trace of dopamine?
adrenal medulla
Another term for sensory division is ______ division.
afferent
Neurons that convey information to the CNS (indicated by the arrow labeled A) are called sensory neurons, or ________________ neurons.
afferent
Which term describes all neurons that carry signals TOWARDS the CNS?
afferent
What factor accounts for the fact that the right side of the brain communicates with the left side of the body, and vice versa?
decussation
The processes that branch from the somas of most neurons are called ______.
dendrites
______________ are the processes of a neuron that usually receive signals from other neurons.
dendrites
__________are the processes of a neuron that usually receive signals from other neurons.
dendrites
During which part of the action potential do most voltage-gated sodium channels open?
depolarization
Which term refers to the upward change in membrane potential during an action potential?
depolarization
Which term refers to how long a stimulus lasts?
duration
Motor, or____________ , neurons carry signals away from the CNS and they lead to effectors (muscle and gland cells).
efferent
Select all that apply Which two organ systems are primarily responsible for coordinating the other bodily systems so as to maintain homeostasis?
endocrine nervous
Two organ systems are dedicated to internal coordination, communication between the other systems, and maintaining the overall homeostasis of the body. They are the _________ system, which communicates by means of hormones, and the ________system which sends quick electrical and chemical messages from cell to cell.
endocrine system nervouse system
Choose the name of the thin layer of fibrous connective tissue found around myelin in nerve fibers of the peripheral nervous system.
endoneurium
Which type of transport is used to move mitochondria, synaptic vesicles, and small molecules such as glucose toward the distal end of an axon?
fast axonal transport
Which order neurons of the spinocerebellar tract originate at muscles and tendons?
first
In a sensory pathway, which neuron detects the stimulus and transmits the signal to the spinal cord or brainstem?
first order
Cell bodies of the sympathetic preganglionic fibers are found in the ________ horn of gray matter in the spinal cord.
lateral
In which column of the spinal cord is the anterior spinocerebellar tract found?
lateral
Select all that apply Which sensory modalities involve the activation of tactile (Merkel) discs?
light touch texture
The myelin sheath is composed mostly of which of the following?
lipid
Inclusions found in neurons include "wear-and-tear" granules that form when lysosomes degrade worn-out organelles and other products. What is the name of the golden-brown pigment that they contain?
lipofuscin
Which term refers to decremental changes in electrical potential along a dendrite or the soma?
local potentials
Regarding the length of fibers, the parasympathetic nervous system has ______ preganglionic fibers and ______ postganglionic fibers.
long short
Which type of glial cell is indicated by the arrow labeled A?
olidendrocytes
What is the alternative name for the craniosacral division of the ANS?
parasympathetic division
Which division of the ANS is associated with normal body maintenance?
parasympathetic division
_________ nerves convey impulses from the sympathetic trunk ganglia to the distal half of the colon, rectum, bladder, and reproductive organs.
pelvic
Taken together, the sensory and motor subdivisions make up which of the following?
peripheral nervous system
Which type of receptor responds to light?
photoreceptor
Which term is used to refer to a cell membrane across which there is a separation of electrical charge, so that one side is more positive and the other side is more negative?
polarized
The third-order neurons of the spinoreticular tract runs from the ______ to the thalamus.
pons
The cuneate fasciculus is located in the ______ column of the spinal cord.
posterior
In the sympathetic division of the ANS the ______ nerve fibers are long while the ______ fibers are short.
postganglionic preganglionic
Which ion has the greatest influence on the resting membrane potential of most neurons?
potassium
An electrical potential is a form of what type of energy?
potential energy
Which parasympathetic fibers are found in the pelvic splanchnic nerves?
preganglionic
The position and movements of body parts is detected by receptors called ______.
proprioceptors
Which term refers to the area within which a single sensory neuron is able to detect a stimulus?
receptive field
The initial effect of a stimulus on a sensory receptor is a small, local change in membrane potential called a(n) ___________ potential.
receptor
Which term refers to any structure specialized to detect a stimulus?
receptor
Which term refers to a local, stimulus-induced change in the membrane potential of a receptor cell?
receptor potential
Which neuroglial cell is found in the peripheral nervous system?
satellite cells
Which pathways are made up of three neurons?
sensory
Select all that apply List the three functional classes of neurons.
sensory interneurons motos
The division of the ANS that has relatively short preganglionic fibers and long postganglionic fibers is the ______ division.
sympathetic
Which division inhibits digestion?
sympathetic
the _______ division of the ANS and the adrenal medulla develop from the same embryonic tissue.
sympathetic
Which type of receptor is specialized to respond to hot and cold stimuli?
thermoreceptor
a _____________ is a receptor that responds to temperature (heat and cold)
thermoreceptor
The sympathetic division of the ANS is also called the ______ division as it arises from the thoracic and lumbar regions of the spinal cord.
thoracolumbar
How many neurons are typically found in an ascending pathway between the receptor and the brain?
three
Which is an example of a general sense?
touch
An axon lacking a myelin sheath is said to be ______.
unmyelinated
Together, the sympathetic and parasympathetic nervous systems make up the entirety of which division of the nervous system?
visceral motor
Which term is another name for the autonomic nervous system?
visceral motor division
Select all that apply Which are examples of sensory modality?
vision hearing taste
Which is most likely to be the resting membrane potential of a neuron?
-70mV
The nervous system plays an important role in maintaining homeostasis. List, in order, the basic steps that describe how the nervous system carries out this task
1. information receive by sensory receptors is transmitted to the CNS 2. info is prcessed and an appropriate response is determined 3. a command is issued to effectors such as muscles or glands
Click and drag on elements in order Place these events into the order in which they occur during a single action potential.
1. local potential depolarizes membrane 2. threshold is reached 3. depolarization spike 4. repolarization 5. hyper polarization
Which best describes an electrical potential?
A form of potential energy that can produce current
Which describes the sympathetic chain ganglia?
A longitudinal series of ganglia adjacent to both sides of the vertebral column
The all-or-none law of action potentials states which of the following?
A neuron will fire at maximum voltage if a stimulus depolarizes it to threshold.
Which nerve tract is indicated in the figure by the letter A?
A) cuneate fasciculus
Which contains both sympathetic and parasympathetic axons that send nerves to the abdominal and pelvic organs? Multiple choice question.
Abdominal aortic plexus
What neurotransmitters do the neurons of the autonomic nervous system secrete?
Acetycholine and norepinephrine
Which are components of a visceral reflex arc? Multiple select question.
Afferent neurons Receptor in the stomach Smooth muscle Efferent neurons
The spinoreticular tract is found in which columns of the spinal cord?
Anterior and lateral
The spinothalamic tract is found in which columns of the spinal cord?
Anterior and lateral
Which nerve tract is indicated in the figure? image labelled
Anterior spinocerebellar tract
What is a receptive field?
Area within which a single sensory neuron is able to detect a stimulus
What type of neuron is shown in the image?
BIPOLAR
Select all that apply Which are characteristics of local potentials?
Decremental Graded
List the fundamental physiological properties of neurons.
Excitability, conductivity, secretion
True or false: Sensory receptors are composed of sensory organs.
FALSE Reason: Sensory organs contain sensory receptors along with accessory tissue.
True or false: Damaged nerve fibers in the CNS regenerate very fast whereas damaged nerve fibers in the PNS never regenerate.
FALSE Reason: Damaged nerve fibers in the CNS cannot regenerate at all, but since the CNS is enclosed in bone, it suffers less trauma than the PNS. Regeneration in the PNS is facilitated by Schwann cells. It may be a slow and not always perfect process.
True or false: All sensory signals are consciously perceived.
FALSE Reason: While many sensory signals travel to the cerebral cortex, and are consciously perceived, others, such as the spinal reflexes, remain subconscious as they only travel to the cord.
Where is the origin of sensory signals carried by the cuneate fasciculus?
From vertebra T6 and up to the brain
Nerve signals carried from the midthoracic and lower parts of the body are carried by which ascending tract?
Gracile fasciculus
Select all that apply Which are somesthetic senses?
Pressure Touch Stretch Pain
Which nervous system regulates conscious, voluntary movements of the skeletal muscles?
Somatic nervous system
Match the following terms with their description. Instructions
axon hillock -A mound located on one side of the soma from which the axon originates axoplasm-Cytoplasm of the axon axolemma-Plasma membrane of the axon axon collateral - Branch that originates from an axon
Which term applies to the small swellings at the distal end of the axon of a neuron that contain synaptic vesicles?
axon terminals
Which term refers to the passage of proteins, organelles and other materials along an axon?
axonal transport
Neurons that have one axon and one dendrite, such as olfactory cells, certain neurons of the retina, and sensory neurons of the inner ear, are classified as which of the following?
bipolar
Sensory (afferent) neurons do which of the following?
carry signals to spinal chord and brain
The brain and spinal cord are components of the ______ nervous system, while the nerves and ganglia are components of the ______ nervous system.
central nervous system peripheral nervous system
Where do signals ascending through the spinocerebellar tract terminate?
cerebellum
Match each type of receptor to the stimulus it detects. Instructions
chemoreceptor - chemicals thermoreceptor - changes in temperature photoreceptor - light nociceptor - tissue damage (or potentially damaging stimuli) mechanoreceptor - touch, pressure, stretch, vibration
Select all that apply Which types of sensory receptors consist of free nerve endings?
cold receptors warm receptors nociceptors
Which fundamental physiological property of neurons allows them to send signals quickly over long distances?
conductivity
Which tract will have its origin and destination of opposite sides of the body?
contralateral
Select all that apply The visceral motor division of the PNS is also called the autonomic division. Which of the following are functions of this division?
controlling gland secretion stimulating smooth muscle accelerating or decreasing heartbeat
The ________ tract carries signals for precise, finely coordinated limb movements.
corticospinal
Which term refers to the FLOW of charged particles from one point to another?
current
Which cell type if indicated by the arrow labeled A?
ependymal
Which glial cell produces and helps circulate cerebrospinal fluid?
ependymal cells
Which cranial nerve regulates secretion from the tear glands,salivary glands, and nasal glands?
facial
The trigger zone includes the axon hillock and the ___________ segment, a region between the axon hillock and the first glial cell.
initial
Which term refers to the segment of an axon between the axon hillock and the first glial cell?
initial segment
The arrow labeled A is pointing to which type of neuron in this diagram?
interneuron
Which type of neuron lies entirely within the CNS and carries out the integrative function of the nervous system?
interneuron
Which nerve tracts do not decussate?
ipsilateral
The neurons indicated by a letter "A" are structurally classified as ______ neurons. The neurons indicated by a letter "B" are structurally classified as ______ neurons.
multipolar, bipolar
Exteroceptors respond to which of the following?
n
Which type of receptor detects touch, pressure, stretch, or vibration?
Mechanoreceptor
What types of stimuli activate nociceptors?
Tissue damage, potentially damaging stimuli
Select all that apply Which are components of a visceral reflex arc?
1. Receptor in the stomach 2. Afferent Neuron 3. Smooth Muscle 4. Efferent Neurons
Select all that apply The area indicated in the figure contains two tracts. What are they?
(bottom bright blue part) ANTEROLATERAL SYSTEM - contains spinothalamic and spinoreticular tracts
Parasympathetic fibers leave the brainstem through which cranial nerves? Select all that apply.
-III -VII -IX -X
Select all that apply After entering the sympathetic chain, preganglionic nerve fibers may do which of the following?
-Immediately synapse with postganglionic fibers -Move up or down the chain and synapse in ganglia at other levels -Pass through the sympathetic chain without synapsing, forming splanchnic nerves
Select all that apply Which are true regarding the Na+-K+ pump?
-It helps maintain the proper ion distribution across the membrane, compensating for ion leakage. -It accounts for about 70% of the energy (ATP) required by the nervous system.
Select all that apply Which statements are true regarding the Na+-K+ pump?
-It helps maintain the proper ion distribution across the membrane. -It requires the use of ATP. -It moves Na+ out of the cell and K+ into the cell. -It accounts for about 70% of the energy (ATP) required by the nervous system
Select all that apply Which correctly describe axonal transport?
-It is bidirectional (retrograde and anterograde transport). -It involves transport of proteins within the axon (i.e. synaptic knob enzymes or proteins that maintain the axolemma).
Select all that apply Which describes slow axonal transport?
-It is used to renew worn-out axoplasmic components in mature neurons. -It works in a stop-and-go fashion.
Select all that apply Which are functions of astrocytes?
-Secrete nerve growth factors -Convert blood glucose to lactate for neurons to use for fuel -Form blood-brain barrier -Regulate chemical composition of tissue fluid
Select all that apply Which are properties of action potentials?
-Self-propagating -Nondecremental (signal maintains amplitude) -All or none
Select all that apply Which of the following statements are true about sodium?
-The resting plasma membrane is much less permeable to Na+ than to K+. -Na+ is about 12 times as concentrated in the ECF as in the ICF.
Select all that apply Which statements are true about Schwann cells?
-They form the myelin sheath in the PNS. -They form the neurilemma. -They assist in the regeneration of damaged nerve fibers.
Click and drag on elements in order List in chronological order the stages of regeneration of a nerve fiber.
1. degeneration of axon and myelin distal to injury2. swelling of soma; dispersal of Nissl bodies3. sprouting of axon growth processes4. growth process enters regeneration tube5. reestablishment of synaptic contact
Click and drag on elements in order Place the components of a visceral reflex arc in order.
1. receptor 2. afferent neuron 3. interneuron 4. efferent neurons 5. effector
What is the approximate ratio of glial cells to neurons?
10:1
How many major collateral ganglia are found on the aorta?
3
Which is usually under involuntary control?
Autonomic nervous system
What is the background activity of both the sympathetic and parasympathetic divisions of the ANS called?
Autonomic tone
From which regions of the CNS do the nerves of the parasympathetic nervous system arise?
Brainstem Sacral division of spinal cord
How does the brain determine the location of a stimulus?
By which axons send the signal to the CNS
Which plexuses receive parasympathetic fibers from the vagus nerve?
Cardiac plexus Esophageal plexus Pulmonary plexus
What are the three collateral ganglia of the abdominal plexus?
Celiac, superior mesenteric, and inferior mesenteric
What are the two major anatomical subdivisions of the nervous system?
Central and peripheral nervous systems
Visceral effectors exhibit denervation _________ when their nerves are severed.
Hypersensitivity
Where does the first-order neuron of the spinothalamic tracts end?
In the posterior horn at the point of entry
Which of the following occurs during the fight-or-flight response?
Increased ATP production
Electrical currents in neurons are due primarily to the flow of which of the following through gated channels?
Ions such as sodium and potassium
Slow axonal transport is always anterograde. What about fast axonal transport?
It can be either anterograde or retrograde.
At rest, K+ diffuses out of the cell through leak channels in the plasma membrane. Why does K+ diffusion result in a negative membrane potential?
It creates a slight local accumulation of K+ on the outside of the membrane relative to the inside.
Which describes a preganglionic neuron in the ANS?
It has its cell body in the spinal cord or the brainstem and its axon terminates in a ganglion.
Which term refers to the brain's ability to determine the site of stimulation?
Location -encpded by which nerve fibers issue signals to the brain NOT MODALITY Reason: Duration refers to how long a stimulus lasts. NOT INTENSITY Reason: Firing frequency (ie. the rate of action potential production) determines the intensity of a stimulus.
Neurons with numerous dendrites and a single axon are structurally classified as which of the following?
MULTIPOLAR
Select all that apply Choose the major cytoplasmic inclusions in a neuron.
Melanin Lipid droplets Lipofuscin Glycogen granules
Proprioceptors respond to which type of stimuli?
Movements or changes in body position
Where do the first-order neurons of the spinocerebellar tract originate?
Muscles and tendons
Select all that apply Which describes the axons of the white communicating ramus?
Myelinated Preganglionic Sympathetic
Parasympathetic fibers leave the brainstem through which cranial nerves? Select all that apply.
Oculomotor Facial Glossopharyngeal Vagus
After spraying perfume on her neck, Tasha becomes less aware of the scent over time. What property is this describing?
Sensory adaptation
Which glial cell insulates nerve fibers from extracellular fluids and speeds up signal conduction in the brain?
Oligodendrocytes
Which division of the ANS is referred to as the "rest and digest" division?
Parasympathetic
Which term is another name for hair receptors?
Peritrichial endings
Which type of neurons make up the adrenal medulla?
Postganglionic sympathetic
Select all that apply Which factors influence the speed of nerve signal conduction?
Presence of myelin Diameter of axon
Which of the following contributes to the development of the resting membrane potential in neurons?
Reason: K+ is more concentrated in the ICF and Na+ is more concentrated in the ECF.
After a nerve cell responds to a stimulus, the period of time when the cell can not respond again except to an unusually strong stimulus is called what?
Relative refractory period not absolute: Recall that the absolute refractory period occurs after a nerve cell responds to a stimulus. It is the period of time when the cell can not respond again, regardless of the strength of stimulus.
Match each point in the action potential to the corresponding description of voltage-gated sodium and potassium channel activity.
Resting Membrane Potential - Choice, Both types of voltage-gated channels are closed. Both types of voltage-gated channels are closed. Depolarization Begins - Choice, Voltage-gated Na+ channels open; voltage-gated K+ channels open more slowly Voltage-gated Na+ channels open; voltage-gated K+ channels open more slowly Repolarization begins - Choice, Voltage-gated Na+ channels inactivate; voltage-gated K+ channels remain open longer Voltage-gated Na+ channels inactivate; voltage-gated K+ channels remain open longer
Select all that apply Which are usually found inside the cell body (or soma) of a mature neuron?
Rough endoplasmic reticulum Mitochondria Nucleus
Which term refers to sensory receptors accompanied by accessory tissues that facilitate transduction of a stimulus?
Sense organ
True or false: Action potentials occur only where there are voltage-gated ion channels.
TRUE Reason: If an excitatory local potential arrives at the trigger zone where the voltage-gated channels are more abundant, it can generate an action potential
True or false: The neuron shown in this picture is structurally classified as an anaxonic neuron.
TRUE Reason: The neuron shown in this picture has multiple dendrites but no axons and it is classified as anaxonic. (The prefix "an-" is a negative, so the term means "no axon".)
True or false: As long as there is an electrical potential across a cell membrane, we say that the membrane is polarized.
TRUE Reason: The term polarized refers to a separation of charge, with one side more positive and the other side more negative.
Which part of the neuron is indicated by the arrow labeled A?
Terminal arborization
What does contralateral mean?
That two points are on opposite sides of the body.
A negative membrane potential indicates which of the following?
The inside of the membrane is negatively charged relative to the outside.
which best describes an electrical current
The movement of charged particles like ions
In order for a peripheral nerve fiber to regenerate it must have which of the following?
The soma and at least some neurilemma intact
Which are true about action potentials?
They usually cannot be stopped once they have begun (irreversible).
Which efferent pathway has a single nerve fiber extending from the CNS to effector?
Thoracic and lumbar regions of the spinal cord
Which lists the STRUCTURAL categories of neurons?
Unipolar, bipolar, anaxonic, and multipolar
Select all that apply Which sensations result primarily from the activation of exteroceptors?
Vision hearing cutaneous sensations
What letter is the preganglionic nerve fiber labeled in the figure?
a
Which nerve tract is indicated in the figure?
a) gracile fasciculus
Which image is depicting somatic efferent innervation? Multiple choice question.
a. somatic bending innvervention
The ______ is a network of sympathetic and parasympathetic axons that wrap around the aorta.
abdominal aortic plexus
The refractory period in which no stimulus of any strength will trigger a new action potential is the ______ refractory period.
absolute
What does the axon of a postganglionic neuron synapse with?
an effector
Neurons that have multiple dendrites but no axons, and which do not produce action potentials, are called ______ neurons.
anaxonic
The spinoreticular tract is part of the _____________ system in the anterior and lateral columns.
anterolateral
The spinothalamic tract is part of the ______ system in the anterior and lateral columns.
anterolateral
What is a receptive field?
area within which a single sensory neuron is able to detect a stimulus
Within the spinal cord, which tracts carry information up to the brain?
ascending
What type of glial cell is indicated by the arrow labeled A?
astrocytes
Which type of cell plays a role in the establishment of the blood-brain barrier?
astrocytes
The _______ nervous system controls the activity of glands, cardiac muscle, and smooth muscle.
autonomic
The sympathetic and parasympathetic systems exhibit a background rate of activity referred to as _________ tone.
autonomic
Which nervous system has two nerve fibers connecting the CNS to an effector?
autonomic
Which nervous system controls glands, smooth muscle, and cardiac muscle?
autonomic nervous system
Name the area of the neuron indicated by the arrow labeled A.
axon collateral
Because the nerve tracts of the spinal cord undergo ________ , the right side of the brain communicates with the left side of the body, and vice versa.
decussation
The plural form of ganglion is ______.
ganglia
The knotlike swelling in a nerve where neuron cell bodies are found is called a(n)
ganglion
______ cells protect the neurons and help them function.
glial
Select all that apply Which types of glial cells are found in the central nervous system?
glial (neuroglia) Astrocytes Microglia Oligodendrocytes Ependymal cells
the ________ nerve carries parasympathetic fibers to the parotid salivary gland.
glossopharyngeal
Where do the nerve fibers of the gracile fasciculus terminate in the medulla oblongata?
gracile nucleus
The ______ communicating ramus carries unmyelinated sympathetic postganglionic fibers that exit the ganglion, enter a spinal nerve, and then travel to the target organ.
gray
Which type of nerve ending detects deflection (bending) of body hair?
hair receptors
A shift in membrane voltage to a value that is more negative than the resting membrane potential is called ______.
hyperpolarization
This image shows an action potential. What is indicated by the green arrow?
hyperpolarization of the membrane
What is the primary function of the myelin sheath?
increase speed of signal conduction in the axon
Between the nodes of Ranvier are myelin-covered segments of axon encircled by Schwann cells. Which term refers to these segments?
internodes
Fibers from the cuneate fasciculus end on the ______ side of the medulla oblongata.
ipsilateral
Which tract will have its origin and destination on the same side of the body?
ipsilateral
During axonal transport, motor proteins transport material as they crawl along microtubules. Match the type of axonal transport with its corresponding motor protein. Instructions
kinesin --> anterograde transport dynein --> retrograde transport
In descending pathways, the upper motor neurons synapse with ______ motor neurons in the brainstem or spinal cord.
lower
Most encapsulated nerve endings are ______.
mechanoreceptors
Which type of glial cells in the central nervous system fight microorganisms and destroy foreign matter and dead nervous tissue?
microglia
Which cell is indicated by the arrow labeled A?
microglial cell
Which term refers to the type of stimulus or sensation produced when a sensory receptor is activated?
modality
Within the spinal cord, what type of information do the descending tracts carry?
motor
Which division of the PNS carries signals from the CNS to glands and muscle cells?
motor (visceral motos division)
What creates electrical currents in neurons?
movement of ions through channels
Neurons are classified structurally according to the number of processes extending from the soma. Match each classification to its description. Instructions
multipolar nerons --> one axon;multiple dendrites bipolar neurons--> one axon;one dendrite unipolar neurons --> a single process anaxonic neurons--> no axon; multiple dendrites
What are the effectors of motor neurons?
muscles and glands
Which term refers to the thick outermost coil of a Schwann cell?
neurilemma
The ______ (the cell body of a neuron) gives rise to branch-like processes called ______, which are the primary sites for receiving signals from other neurons.
neurosome dendrites
Which type of receptor is involved in the sensation of pain?
nociceptor
Which term refers to the gaps between segments of myelin along an axon?
nodes of ranvier
At rest, K+ diffuses out of the cell through leak channels, resulting in a slight local accumulation of positive charge on the outside of the membrane (due to excess K+) and a slight local accumulation of negative charge on the inside of the membrane (due to decreased K+). This describes the basis of the ____________ membrane potential.
resting
The second-order neurons of the spinoreticular tract terminate in the __________ formation of the brainstem.
reticular
Which type of axonal transport involves movement up the axon toward the soma?
retrograde Reason: Recall that retrograde transport moves material toward the soma and anterograde transport moves material away from the soma down the axon.
Which regions of the CNS does the parasympathetic division of the ANS arise from?
sacral spinal chord brainstem
______ cells are glial cells in the peripheral nervous system that surround somas of neurons in the ganglia, provide electrical insulation, and regulate the chemical environment of neurons.
satellite
Match each glial cell type with its location and function. Instructions
satellite cells- Choice, In the PNS; surround somas of neurons in ganglia, provide electrical insulation, and regulate the chemical environment of neurons In the PNS; surround somas of neurons in ganglia, provide electrical insulation, and regulate the chemical environment of neurons schwann cells- Choice, In the PNS; form neurilemma around all PNS fibers and myelin around most of them; aid in regeneration of damaged nerve fibers. In the PNS; form neurilemma around all PNS fibers and myelin around most of them; aid in regeneration of damaged nerve fibers. ependymal cells- Choice, In the CNS; line cavities of the brain and spinal cord; secrete and circulate CSF In the CNS; line cavities of the brain and spinal cord; secrete and circulate CSF microglia - Choice, In the CNS; phagocytize microorganisms, foreign matter, and dead nervous tissue In the CNS; phagocytize microorganisms, foreign matter, and dead nervous tissue
Which two types of neuroglia are found only in the peripheral nervous system?
schwann and satellite cells
Which type of glial cell aids in regeneration of damaged peripheral nerve fibers by forming a regeneration tube to help reestablish the former connection?
schwann cells
Which type of glial cell produces the myelin sheath in the PNS?
schwann cells
In the spinothalamic tract, the ______ -order neurons decussate from the posterior horn of the spinal cord.
second
In a sensory pathway, which neurons run from the spinal cord or brainstem to the thalamus?
second-order
The release of a neurotransmitter is an example of which physiological property exhibited by a neuron?
secretion
Which term refers to the conscious perception of a stimulus?
sensation
Afferent neurons are ______ neurons.
sensory
Which type of neuron begins in most body organs and carries information toward the central nervous system?
sensory neuron
Select all that apply Which sensory modalities depend on the activation of chemoreceptors?
smell taste
Neurons in which nervous system division secrete only acetylcholine?
somatic
Which nervous system division has skeletal muscles as effectors?
somatic
The motor division of the PNS is further subdivided into the ______ motor division that carries signals to the skeletal muscles and the ______ motor division (also known as the autonomic nervous system), which carries signals to glands, cardiac muscle, and smooth muscle.
somatic visceral
The sensory division of the PNS is further subdivided into the ______ sensory division, which carries signals from receptors in the skin, muscles, bones, and joints, and the ______ sensory division, which carries signals from organs of the thoracic and abdominal cavities.
somatic visceral
The SENSORY and MOTOR divisions of the peripheral nervous system are further split into which two subdivisions?
somatic and visceral
vision is a ______ sense
special
Senses in which of the following categories utilize receptors that are specific to a particular area of the body?
special senses
The tract indicated by the letter A is the posterior ______ tract.
spinocerebellar
Preganglionic sympathetic fibers typically synapse with sympathetic chain ganglia unless they pass through, forming _________ nerves that instead enter collateral ganglia.
splanchnic
Which division of the ANS is responsible for increasing heart rate, alertness, blood pressure, pulmonary airflow, blood-glucose concentration, and blood flow to the heart and skeletal muscles?
sympathetic
What are the two divisions of the VISCERAL motor division?
sympathetic and parasympathetic
Which are specialized to detect textures, edges and shapes?
tactile (merkel) discs
At its distal end, an axon has an extensive complex of fine branches called a(n) ______.
terminal arborization
Where do the third-order neurons of the spinoreticular tract run from the pons to?
thalamus
If the nerves to visceral effectors are severed, what happens to the effectors?
the become hypersensitive
What is sensory adaptation?
the decrease in perceived sensation over time
Select all that apply Which are examples of somatosensory (general) senses?
touch, pressure, stretch, heat, cold and pain
What is the primary function of a sensory receptor?
transduction
______ is the conversion of one form of energy to another. In biology, it is used to describe the conversion of stimulus energy into an electrical signal in the nervous system.
transduction
The axon hillock and initial segment play an important role in initiating a nerve signal. They are collectively called the ___________ zone.
trigger
The region indicated by the circle is the ______. It plays an important role in initiating a nerve signal. It is formed by the axon hillock and the initial segment.
trigger zone
The number of neurons in a descending pathway is ___________
two 2
Select all that apply What are the characteristics of a visceral reflex?
unconscious automatic stereotyped
Neurons with a single process extending from the soma, such as the neurons that carry sensory signals to the spinal cord, are classified structurally as ______ neurons.
unipolar
Which type of neuron has one single process that branches like a T into a peripheral fiber and a central fiber?
unipolar
Consider the two motor neurons that form descending pathways. The neurons called the _________ motor neurons have their somas in the cerebral cortex or brainstem.
upper
In descending tracts, which motor neuron innervates the target organ?
upper
Select all that apply Which sensations result from activation of interoceptors?
visceral pain bladder pressure detect stimuli in the internal organs such as stomach intestines and bladdes, and produce feelings of stretch, pressure, visceral pain, and nausea.
Select all that apply What information does the brain use to determine the intensity of a stimulus?
which sensory neurons respond how many sensory neurons respond how rapidly the sensory neurons fire