NU 545 Unit 2 | LATEST UPDATED| REAL EXAM QUESTIONS AND
ANSWERS | 100% RATED CORRECT | 100% VERFIED | ALREADY GRADED
A+
Review the anatomy of the brain. Which portion is responsible for keeping you
awake, controlling thought, speech, emotions and behavior, maintaining balance and
posture? - (ANSWERS)The reticular formation is a large network of diffuse nuclei
that connect the brainstem to the cortex and control vital reflexes. It is essential for
maintaining wakefulness and is referred to as the reticular activating system. Some
nuclei within the reticular formation support specific motor movements, such as
balance and posture (p448). The cerebellum is responsible for maintaining balance
and posture (p452). The prefrontal area is responsible for the elaboration of thought
(pg 449). The Broca speech area is on the inferior frontal gyrus (Brodmann 44, 45).
It is usually on the left hemisphere and is responsible for motor aspects of speech.
Broca Area in the inferior frontal lobe (Brodmann areas 44, 45) is an important
center for speech and language processing. This area, rostral to the inferior edge of
the premotor area (Brodmann area 6). Injury to this area results in difficulty forming
or inability to for words (expressive aphasia or dysphasia). Wernicke (posterior
Brodmann 22) and adjacent portions of the parietal lobe are a sensory speech area,
responsible for reception and interpretation of speech (aphasia/dysphasia). Insula
(insular lobe) between hemispheres temporal and frontal lobes, processes emotional
information (pg 450). The basal ganglia nuclei are important for emotional functions
(pg 451). Cerebrum > forebrain/hindbrain
Broca's area = difficulty writing and finding words, See chart 17.10 (p523)
Know the function of the arachnoid villi. - (ANSWERS)The arachnoid villi protrude
from the arachnoid space, through the dura mater, and lie within the blood flow of
the venous sinuses. The villi function as one-way valves directing CSF outflow into
the blood but preventing blood flow into the subarachnoid space. Thus CSF is
formed from the blood and, after circulating throughout the CNS, it returns to the
blood. Absorbs CSF (pg 459)
Where is the primary defect in Parkinson's disease and Huntington's? -
(ANSWERS)Extrapyramidal system; controls motor system (involuntary
, NU 545 Unit 2 | LATEST UPDATED| REAL EXAM QUESTIONS AND
ANSWERS | 100% RATED CORRECT | 100% VERFIED | ALREADY GRADED
A+
movement) (pg 451). Substantia nigra (of the midbrain) synthesizes dopamine. The
dysfunction of dopamine neurons is associated with PD and Huntington's
What is the function of the CSF? Where is it produced? Where is it absorbed? -
(ANSWERS)Cerebrospinal fluid (CSF) is a clear, colorless fluid similar to blood
plasma and interstitial fluid. The intracranial and spinal cord structures float in CSF
and are thereby partially protected from jolts and blows. The buoyant properties of
the CSF also prevent the brain from tugging on meninges, nerve roots, and blood
vessels. Appx 600ml is produced daily (457). Ependymal cells in the choroid
plexuses are the structures that produce CSF; they arise from the pia mater. The
arachnoid villi reabsorb the CSF (p458)
Review blood flow to the brain. - (ANSWERS)The brain receives approximately
20% of the cardiac output, or 800 to 1000 ml of blood flow per minute.
Autoregulated to maintain a stable flow during fluctuating perfusion pressures.
Carbon dioxide serves as a primary regulator for blood flow within the CNS. It is a
potent vasodilator in the CNS, and its effects ensure an adequate blood supply. The
brain derives its arterial supply from the internal carotid arteries (anterior
circulation) and the vertebral arteries (posterior circulation) (Fig. 15.20). The
internal carotid arteries supply a proportionately greater amount of blood flow. They
originate at the common carotid arteries, enter the cranium through the base of the
skull, and pass through the cavernous sinus. After entering the skull, these arteries
divide into the anterior and middle cerebral arteries (Fig. 15.21). The vertebral
arteries originate at the subclavian arteries and pass through the transverse foramina
of the cervical vertebrae, entering the cranium through the foramen magnum. They
join at the junction of the pons and medulla oblongata to form the basilar artery. The
basilar artery divides at the level of the midbrain to form paired posterior cerebral
arteries (459). When one of the routes is obstructed, the circle of Willis is an
alternate route.
, NU 545 Unit 2 | LATEST UPDATED| REAL EXAM QUESTIONS AND
ANSWERS | 100% RATED CORRECT | 100% VERFIED | ALREADY GRADED
A+
What is the gate control theory of pain? - (ANSWERS)Gate control theory (GCT)
integrates and builds upon features of the other theories to explain the complex
multidimensional aspects of pain perception and pain modulation. Pain transmission
is modulated by a balance of impulses conducted to the spinal cord where cells in
the substantia gelatinosa function as a "gate." The spinal gate regulates pain
transmission to higher centers in the CNS. Large myelinated A-delta fibers and
small unmyelinated C fibers respond to a broad range of painful stimuli
(mechanical, thermal, and chemical). These fibers terminate on interneurons in the
substantia gelatinosa (laminae in the dorsal horn of the spinal cord) and "open" the
spinal gate to transmit the perception of pain. Closure or partial closure of the spinal
gates can occur from nonnociceptive stimulation (i.e., from touch sensors in the
skin) carried on large A-beta fibers decreasing pain perception.
The theories of pain include the specificity theory, pattern theory, gate control
theory, and neuromatrix theory. 4 Specificity theory proposes that pain and touch are
carried on distinct pathways that project to distinct brain centers. Injury activates
only specific pain receptors and fibers that project to the brain. Intensity of pain is
directly related to the amount of associated tissue injury (i.e., pricking one's finger
with a needle would cause minimal pain, whereas cutting one's hand with a knife
would produce more pain). The theory is useful when applied to specific injuries and
the acute pain associated with them. It does not account for chronic pain or cognitive
and emotional elements that contribute to more complex types of pain. 5
Know the type of nerve fibers that transmit pain impulses. Page 470 -
(ANSWERS)Transduction begins when nociceptors are activated by a painful
stimulus causing ion channels to open, creating electrical impulses that travel
through axons or two primary types. Pain impulses are conducted along the A-delta
and C fibers of nociceptors.
A-delta fibers: larger myelinated fibers that rapidly transmit sharp, well-localized
"fast" sensations (intense heat or pinprick) "reflex"
· stimulated by mechanoreceptors and mechanothermal nociceptors
ANSWERS | 100% RATED CORRECT | 100% VERFIED | ALREADY GRADED
A+
Review the anatomy of the brain. Which portion is responsible for keeping you
awake, controlling thought, speech, emotions and behavior, maintaining balance and
posture? - (ANSWERS)The reticular formation is a large network of diffuse nuclei
that connect the brainstem to the cortex and control vital reflexes. It is essential for
maintaining wakefulness and is referred to as the reticular activating system. Some
nuclei within the reticular formation support specific motor movements, such as
balance and posture (p448). The cerebellum is responsible for maintaining balance
and posture (p452). The prefrontal area is responsible for the elaboration of thought
(pg 449). The Broca speech area is on the inferior frontal gyrus (Brodmann 44, 45).
It is usually on the left hemisphere and is responsible for motor aspects of speech.
Broca Area in the inferior frontal lobe (Brodmann areas 44, 45) is an important
center for speech and language processing. This area, rostral to the inferior edge of
the premotor area (Brodmann area 6). Injury to this area results in difficulty forming
or inability to for words (expressive aphasia or dysphasia). Wernicke (posterior
Brodmann 22) and adjacent portions of the parietal lobe are a sensory speech area,
responsible for reception and interpretation of speech (aphasia/dysphasia). Insula
(insular lobe) between hemispheres temporal and frontal lobes, processes emotional
information (pg 450). The basal ganglia nuclei are important for emotional functions
(pg 451). Cerebrum > forebrain/hindbrain
Broca's area = difficulty writing and finding words, See chart 17.10 (p523)
Know the function of the arachnoid villi. - (ANSWERS)The arachnoid villi protrude
from the arachnoid space, through the dura mater, and lie within the blood flow of
the venous sinuses. The villi function as one-way valves directing CSF outflow into
the blood but preventing blood flow into the subarachnoid space. Thus CSF is
formed from the blood and, after circulating throughout the CNS, it returns to the
blood. Absorbs CSF (pg 459)
Where is the primary defect in Parkinson's disease and Huntington's? -
(ANSWERS)Extrapyramidal system; controls motor system (involuntary
, NU 545 Unit 2 | LATEST UPDATED| REAL EXAM QUESTIONS AND
ANSWERS | 100% RATED CORRECT | 100% VERFIED | ALREADY GRADED
A+
movement) (pg 451). Substantia nigra (of the midbrain) synthesizes dopamine. The
dysfunction of dopamine neurons is associated with PD and Huntington's
What is the function of the CSF? Where is it produced? Where is it absorbed? -
(ANSWERS)Cerebrospinal fluid (CSF) is a clear, colorless fluid similar to blood
plasma and interstitial fluid. The intracranial and spinal cord structures float in CSF
and are thereby partially protected from jolts and blows. The buoyant properties of
the CSF also prevent the brain from tugging on meninges, nerve roots, and blood
vessels. Appx 600ml is produced daily (457). Ependymal cells in the choroid
plexuses are the structures that produce CSF; they arise from the pia mater. The
arachnoid villi reabsorb the CSF (p458)
Review blood flow to the brain. - (ANSWERS)The brain receives approximately
20% of the cardiac output, or 800 to 1000 ml of blood flow per minute.
Autoregulated to maintain a stable flow during fluctuating perfusion pressures.
Carbon dioxide serves as a primary regulator for blood flow within the CNS. It is a
potent vasodilator in the CNS, and its effects ensure an adequate blood supply. The
brain derives its arterial supply from the internal carotid arteries (anterior
circulation) and the vertebral arteries (posterior circulation) (Fig. 15.20). The
internal carotid arteries supply a proportionately greater amount of blood flow. They
originate at the common carotid arteries, enter the cranium through the base of the
skull, and pass through the cavernous sinus. After entering the skull, these arteries
divide into the anterior and middle cerebral arteries (Fig. 15.21). The vertebral
arteries originate at the subclavian arteries and pass through the transverse foramina
of the cervical vertebrae, entering the cranium through the foramen magnum. They
join at the junction of the pons and medulla oblongata to form the basilar artery. The
basilar artery divides at the level of the midbrain to form paired posterior cerebral
arteries (459). When one of the routes is obstructed, the circle of Willis is an
alternate route.
, NU 545 Unit 2 | LATEST UPDATED| REAL EXAM QUESTIONS AND
ANSWERS | 100% RATED CORRECT | 100% VERFIED | ALREADY GRADED
A+
What is the gate control theory of pain? - (ANSWERS)Gate control theory (GCT)
integrates and builds upon features of the other theories to explain the complex
multidimensional aspects of pain perception and pain modulation. Pain transmission
is modulated by a balance of impulses conducted to the spinal cord where cells in
the substantia gelatinosa function as a "gate." The spinal gate regulates pain
transmission to higher centers in the CNS. Large myelinated A-delta fibers and
small unmyelinated C fibers respond to a broad range of painful stimuli
(mechanical, thermal, and chemical). These fibers terminate on interneurons in the
substantia gelatinosa (laminae in the dorsal horn of the spinal cord) and "open" the
spinal gate to transmit the perception of pain. Closure or partial closure of the spinal
gates can occur from nonnociceptive stimulation (i.e., from touch sensors in the
skin) carried on large A-beta fibers decreasing pain perception.
The theories of pain include the specificity theory, pattern theory, gate control
theory, and neuromatrix theory. 4 Specificity theory proposes that pain and touch are
carried on distinct pathways that project to distinct brain centers. Injury activates
only specific pain receptors and fibers that project to the brain. Intensity of pain is
directly related to the amount of associated tissue injury (i.e., pricking one's finger
with a needle would cause minimal pain, whereas cutting one's hand with a knife
would produce more pain). The theory is useful when applied to specific injuries and
the acute pain associated with them. It does not account for chronic pain or cognitive
and emotional elements that contribute to more complex types of pain. 5
Know the type of nerve fibers that transmit pain impulses. Page 470 -
(ANSWERS)Transduction begins when nociceptors are activated by a painful
stimulus causing ion channels to open, creating electrical impulses that travel
through axons or two primary types. Pain impulses are conducted along the A-delta
and C fibers of nociceptors.
A-delta fibers: larger myelinated fibers that rapidly transmit sharp, well-localized
"fast" sensations (intense heat or pinprick) "reflex"
· stimulated by mechanoreceptors and mechanothermal nociceptors
