Nervous Tissue and Brain Flashcards

Barbara Herlihy. (2020). The Human Body in Health and Illness (7th Edition) [Texidium version]. Retrieved from http://texidium.com (283 cards)

1
Q

Thinking great thoughts, feeling, moving, seeing, hearing, responding, planning, remembering, being aware of environmental cues, and so much more are functions performed by the ___ system.

(Herlihy, 2020, p. 175)

A

nervous

(Herlihy, 2020, p. 175)

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2
Q

The structures of the nervous system are divided into two parts: the ___ ___ ___ (___) and the ___ ___ ___ (___).

(Herlihy, 2020, p. 175)

A

central nervous system (CNS)

peripheral nervous system (PNS)

(Herlihy, 2020, p. 175)

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3
Q

The central nervous system (CNS) includes the ___ and the ___ ___.

(Herlihy, 2020, p. 175)

A

brain

spinal cord

(Herlihy, 2020, p. 175)

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4
Q

The central nervous system (CNS) is located in the ___ cavity.

The brain is located in the ___ cavity; the spinal cord is enclosed in the ___cavity.

(Herlihy, 2020, p. 175)

A

dorsal

cranial

spinal

(Herlihy, 2020, p. 175)

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5
Q

What is located outside the central nervous system (CNS) and consists of the nerves that connect the central nervous system (CNS) with the rest of the body?

(Herlihy, 2020, p. 175)

A

Peripheral Nervous System (PNS)

(Herlihy, 2020, p. 175)

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6
Q

Nervous System

(Herlihy, 2020, p. 176)

A

(Herlihy, 2020, p. 176)

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7
Q

The nervous system performs three general functions: a ___ function, an ___ function, and a ___.

(Herlihy, 2020, p. 175)

A

sensory

integrative

motor

(Herlihy, 2020, p. 175)

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8
Q

___ nerves gather information from inside the body and from the outside environment.

The nerves then carry the information to the central nervous system (CNS).

For example, information about a cat is picked up by special cells in the boy’s eye and transmitted to the brain.

(Herlihy, 2020, p. 175)

A

Sensory

(Herlihy, 2020, p. 175)

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9
Q

Sensory information brought to the central nervous system (CNS) is interpreted.

The brain not only sees the cat but also does much more.

It recalls very quickly how a cat behaves.

It may determine that the cat is acting hungry or is distressed and ready to attack.

The brain ___, or puts together, everything it knows about cats and then makes its plan.

(Herlihy, 2020, p. 175)

A

integrates

(Herlihy, 2020, p. 175)

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10
Q

___ nerves convey information from the central nervous system (CNS) toward the muscles and glands of the body.

(Herlihy, 2020, p. 176)

A

Motor

(Herlihy, 2020, p. 176)

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11
Q

___ nerves carry out the plans made by the central nervous system (CNS).

For example, the boy decides to feed the hungry cat.

Information must travel along the ___ nerves from the central nervous system (CNS) to all the skeletal muscles needed to feed the cat.

The ___ nerves convert the plan into action.

(Herlihy, 2020, p. 176)

A

Motor

motor

motor

(Herlihy, 2020, p. 176)

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12
Q

Three Functions of the Nervous System

(Herlihy, 2020, p. 177)

A

(Herlihy, 2020, p. 177)

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13
Q

Nervous tissue is composed of two types of cells: the ___ and the ___.

(Herlihy, 2020, p. 176)

A

neuroglia

neurons

(Herlihy, 2020, p. 176)

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14
Q

___, or ___ cells, are the nerve glue.

(Herlihy, 2020, p. 177)

A

Neuroglia

glial

(Herlihy, 2020, p. 177)

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15
Q

___ are the most abundant of the nerve cells; most are located in the central nervous system (CNS).

(Herlihy, 2020, p. 177)

A

Neuroglia

Glial

(Herlihy, 2020, p. 177)

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16
Q

___ cells support, protect, insulate, nourish, and generally care for the delicate neurons.

(Herlihy, 2020, p. 177)

A

Neuroglia

Glial

(Herlihy, 2020, p. 177)

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17
Q

Some of the glial cells participate in ___; others assist in the secretion of ___ ___ (___).

The glial cells, however, do not conduct nerve impulses.

(Herlihy, 2020, p. 177)

A

phagocytosis

cerebrospinal fluid (CSF)

(Herlihy, 2020, p. 177)

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18
Q

Two of the more common glial cells are the ___ and the ___ cells.

(Herlihy, 2020, p. 177)

A

astrocytes

ependymal

(Herlihy, 2020, p. 177)

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19
Q

The star-shaped ___ are the most abundant of the glial cells and have the most diverse functions; they support the neurons structurally, cover the entire surface of the brain, and help form a protective barrier, called the ___-___ barrier.

This barrier helps prevent toxic substances in the blood from entering the nervous tissue of the brain and spinal cord.

(Herlihy, 2020, p. 177)

A

astrocytes

blood–brain

(Herlihy, 2020, p. 177)

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20
Q

___ secrete nerve growth factors that promote neuron growth and enhance synaptic development.

(Herlihy, 2020, p. 177)

A

Astrocytes

(Herlihy, 2020, p. 177)

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21
Q

A second glial cell is the ___ cell.

These cells line the inside cavities of the brain and assist in the formation of cerebrospinal fluid (CSF).

(Herlihy, 2020, p. 177)

A

ependymal

(Herlihy, 2020, p. 177)

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22
Q

Because glial cells undergo ___, most primary central nervous system (CNS) tumors are composed of glial cells, such as astrocytomas.

(Herlihy, 2020, p. 177)

A

mitosis

(Herlihy, 2020, p. 177)

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23
Q

Neuroglia

(Herlihy, 2020, p. 177)

A

(Herlihy, 2020, p. 177)

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24
Q

Correct Spot?

(Herlihy, 2020, p. 178)

A

(Herlihy, 2020, p. 178)

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25
The second type of cell within the nervous system is the ___. Of the two types of nerve cells, the ___ is the most important in the transmission of electrical signals. ## Footnote (Herlihy, 2020, p. 177)
neuron neuron ## Footnote (Herlihy, 2020, p. 177)
26
The ___ enables the nervous system to act as a vast communication network. ## Footnote (Herlihy, 2020, p. 177)
neuron ## Footnote (Herlihy, 2020, p. 177)
27
___ have many shapes and sizes. Some are extremely short; others are very long, with some measuring 4 feet in length. ## Footnote (Herlihy, 2020, p. 177)
Neurons ## Footnote (Herlihy, 2020, p. 177)
28
Unlike glial cells, neurons are ___ and therefore do not replicate or replace themselves when injured. ## Footnote (Herlihy, 2020, p. 177)
nonmitotic ## Footnote (Herlihy, 2020, p. 177)
29
Because they are ___, neurons generally do not give rise to primary malignant brain tumors. ## Footnote (Herlihy, 2020, p. 177)
nonmitotic ## Footnote (Herlihy, 2020, p. 177)
30
Neurons are functionally classified as follows: * ___ neurons: they carry information to the central nervous system (CNS) * ___ neurons: they carry information away from the central nervous system (CNS) * ___: they are found only in the central nervous system (CNS) ## Footnote (Herlihy, 2020, p. 177)
Sensory Motor Interneurons ## Footnote (Herlihy, 2020, p. 177)
31
___ form connections between sensory and motor neurons within the central nervous system (CNS). ## Footnote (Herlihy, 2020, p. 177)
Interneurons ## Footnote (Herlihy, 2020, p. 177)
32
___ play an important role in integrating all sensory information and the appropriate motor responses. ## Footnote (Herlihy, 2020, p. 177)
Interneurons ## Footnote (Herlihy, 2020, p. 177)
33
The three parts of the neuron are the ___, ___ ___, and ___. ## Footnote (Herlihy, 2020, p. 178)
dendrites cell body axon ## Footnote (Herlihy, 2020, p. 178)
34
What are treelike structures that receive signals from other neurons and then transmit the signals toward the cell body? ## Footnote (Herlihy, 2020, p. 178)
Dendrites ## Footnote (Herlihy, 2020, p. 178)
35
One neuron may have thousands of ___, whereas other neurons have fewer. The neuron with the greater number can receive signals from many other neurons. ## Footnote (Herlihy, 2020, p. 178)
dendrites ## Footnote (Herlihy, 2020, p. 178)
36
What contains the nucleus and is essential for the life of the cell? ## Footnote (Herlihy, 2020, p. 178)
Cell Body ## Footnote (Herlihy, 2020, p. 178)
37
The ___ ___ usually receives thousands of signals from the dendrites and “decides” on the signal it wants to send to the axon. ## Footnote (Herlihy, 2020, p. 178)
cell body ## Footnote (Herlihy, 2020, p. 178)
38
What is the long extension that transmits signals away from the cell body? ## Footnote (Herlihy, 2020, p. 178)
Axon ## Footnote (Herlihy, 2020, p. 178)
39
The end of the axon undergoes extensive branching to form many axon ___; it is within the axon ___ that the chemical neurotransmitters are stored. ## Footnote (Herlihy, 2020, p. 178)
terminals terminals ## Footnote (Herlihy, 2020, p. 178)
40
An enlarged view of the axon shows several unique structures: the ___ ___, the ___, and the ___ of ___. ## Footnote (Herlihy, 2020, p. 179)
myelin sheath neurilemma **nodes** of **Ranvier** ## Footnote (Herlihy, 2020, p. 179)
41
Most long nerve fibers of both the peripheral and central nervous systems are encased by a layer of white fatty material called the ___ ___. ## Footnote (Herlihy, 2020, p. 179)
myelin sheath ## Footnote (Herlihy, 2020, p. 179)
42
What protects and insulates the axon? ## Footnote (Herlihy, 2020, p. 179)
Myelin ## Footnote (Herlihy, 2020, p. 179)
43
Nerve fibers covered by myelin are said to be ___. Some neurons are not encased in myelin and are called ___ neurons. ## Footnote (Herlihy, 2020, p. 179)
myelinated unmyelinated ## Footnote (Herlihy, 2020, p. 179)
44
What begins during the fourth month of fetal life and continues into the teenage years? ## Footnote (Herlihy, 2020, p. 179)
Myelination ## Footnote (Herlihy, 2020, p. 179)
45
Because some axons of immature motor neurons lack ___, the movements of an infant are slower and less coordinated than those of an older child. ## Footnote (Herlihy, 2020, p. 179)
myelination ## Footnote (Herlihy, 2020, p. 179)
46
Severely restricting the fat intake of an infant or young child is unwise, because the child is still laying down ___. ## Footnote (Herlihy, 2020, p. 179)
myelin ## Footnote (Herlihy, 2020, p. 179)
47
The formation of myelin sheath differs in the peripheral and central nervous systems. Surrounding the axon of a neuron in the peripheral nervous system is a layer of special cells called ___ cells. The ___ cells form the myelin sheath that surrounds the axon. ## Footnote (Herlihy, 2020, p. 179)
Schwann Schwann ## Footnote (Herlihy, 2020, p. 179)
48
The nuclei and cytoplasm of the Schwann cells lie outside the myelin sheath and are called the ___. ## Footnote (Herlihy, 2020, p. 179)
neurilemma ## Footnote (Herlihy, 2020, p. 179)
49
What is important in the regeneration of a severed nerve? ## Footnote (Herlihy, 2020, p. 179)
Neurilemma ## Footnote (Herlihy, 2020, p. 179)
50
In the central nervous system (CNS), the myelin sheath is formed not by Schwann cells but by ___, a type of glial cell. Because there are no Schwann cells, there is no ___. The lack of the ___ surrounding the axons accounts, in part, for the inability of the central nervous system (CNS) neurons to regenerate. Failure of the neurons of the central nervous system (CNS) to regenerate, however, is not fully explained by the lack of ___; other factors include the formation of scar tissue and the lack of critical nerve growth factors. ## Footnote (Herlihy, 2020, p. 179)
oligodendrocytes neurilemma neurilemma neurilemma ## Footnote (Herlihy, 2020, p. 179)
51
What are the axonal areas not covered by myelin that appear at regular intervals along the myelinated axon? ## Footnote (Herlihy, 2020, p. 179)
Nodes of Ranvier ## Footnote (Herlihy, 2020, p. 179)
52
A) Structure of a Neuron B) Structure Surrounding the Axon ## Footnote (Herlihy, 2020, p. 178)
## Footnote (Herlihy, 2020, p. 178)
53
The tissue of the central nervous system (CNS) is white or gray. White matter is white because of the ___ axons, whereas gray matter is made up of ___ axons, ___ ___, ___, and ___. ## Footnote (Herlihy, 2020, p. 179)
myelinated unmyelinated cell bodies interneurons synapses ## Footnote (Herlihy, 2020, p. 179)
54
Sometimes cell bodies appear in small clusters and are given special names. Clusters of cell bodies located in the central nervous system (CNS) are generally referred to as ___. Small clusters of cell bodies in the peripheral nervous system are called ___. For example, patches of gray called the ___ ___ are located in the brain. Sometimes, these patches of gray are called ___ ___, despite their location in the central nervous system (CNS) ## Footnote (Herlihy, 2020, p. 179)
nuclei ganglia basal nuclei basal ganglia ## Footnote (Herlihy, 2020, p. 179)
55
___ allow the nervous system to convey information rapidly from one part of the body to the next. A stubbed toe makes itself known almost immediately. Think of how fast the information travels from your toe, where the injury occurred, to your brain, where the injury is interpreted as pain. ## Footnote (Herlihy, 2020, p. 179)
Neurons ## Footnote (Herlihy, 2020, p. 179)
56
Information is carried along the neuron in the form of a ___ ___. ## Footnote (Herlihy, 2020, p. 179)
nerve impulse ## Footnote (Herlihy, 2020, p. 179)
57
What is an electrical signal that conveys information along a neuron? ## Footnote (Herlihy, 2020, p. 179)
Nerve Impulse ## Footnote (Herlihy, 2020, p. 179)
58
The nerve impulse is called the ___ ___. ## Footnote (Herlihy, 2020, p. 179)
action potential ## Footnote (Herlihy, 2020, p. 179)
59
There are two phases of an action potential: ___ and ___. ## Footnote (Herlihy, 2020, p. 179)
depolarization repolarization ## Footnote (Herlihy, 2020, p. 179)
60
___ ___ ___ refers to the electrical charge difference across the membrane of the resting neuron. The inside of a resting neuron is more negative (−) than the outside (+). The resting cell is said to be ___. As long as the neuron is ___, no nerve impulse is being transmitted. The cell is quiet, or resting. ## Footnote (Herlihy, 2020, p. 179)
Resting membrane potential polarized polarized ## Footnote (Herlihy, 2020, p. 179)
61
When the neuronal membrane is stimulated, a change occurs in the cell’s electrical state. In the resting (polarized) state, the inside of the cell is (negative/positive). When the cell membrane is stimulated, the inside becomes (negative/positive). As the inside of the cell changes from (negative/positive) to (negative/positive), it is said to ___. ## Footnote (Herlihy, 2020, p. 179)
negative positive negative positive depolarize ## Footnote (Herlihy, 2020, p. 179)
62
Very quickly, the inside of the cell again becomes negative; in other words, it returns to its resting state, or ___. ## Footnote (Herlihy, 2020, p. 179)
repolarizes ## Footnote (Herlihy, 2020, p. 179)
63
Unless the cell ___, it cannot be stimulated again. ## Footnote (Herlihy, 2020, p. 179)
repolarizes ## Footnote (Herlihy, 2020, p. 179)
64
The reading inside the unstimulated neuron is negative (−) 90 millivolt (mv) (___ ___ ___). When stimulated, the cell ___, that is, the inside of the cell becomes positive (+20 mv). Immediately the cell ___, that is the inside of the cell returns to its (−) ___ ___ ___. ## Footnote (Herlihy, 2020, p. 180)
resting membrane potential depolarizes repolarizes resting membrane potential ## Footnote (Herlihy, 2020, p. 180)
65
Nerve Impulse (Action Potential) ## Footnote (Herlihy, 2020, p. 180)
## Footnote (Herlihy, 2020, p. 180)
66
What refers to the degree of depolarization that must be attained for the neuron to completely fully depolarize to +20 mv? ## Footnote (Herlihy, 2020, p. 180)
Threshold Potential ## Footnote (Herlihy, 2020, p. 180)
67
If ___ ___ is not achieved by the stimulus, the signal decays, and the cell returns to the resting membrane potential. Under this condition the action potential fails to fire. ## Footnote (Herlihy, 2020, p. 180)
threshold potential ## Footnote (Herlihy, 2020, p. 180)
68
Nerve Impulse (Action Potential) ## Footnote (Herlihy, 2020, p. 181)
## Footnote (Herlihy, 2020, p. 181)
69
The changes associated with the action potential, or nerve impulse, are caused by the movement of specific ions across the cell membrane of the neuron. This is called the ___ ___ of the action potential. ## Footnote (Herlihy, 2020, p. 180)
ionic basis ## Footnote (Herlihy, 2020, p. 180)
70
To understand the diffusion of ions across the axonal membrane, you must remember the following: the chief intracellular cation is ___ (___) and the chief extracellular cation is ___ (___). If the membrane is or becomes permeable to ___ (___), it diffuses outwardly. If the membrane is permeable to ___ (___), it diffuses inwardly. ## Footnote (Herlihy, 2020, p. 180)
potassium (**K+**) sodium (**Na+**) potassium (**K+**) sodium (**Na+**) ## Footnote (Herlihy, 2020, p. 180)
71
The flow of ions is dependent on two factors: the concentration gradients of ___ (___) and ___ (___) and the ___ characteristics of the membrane. ## Footnote (Herlihy, 2020, p. 180)
potassium (**K+**) sodium (**Na+**) permeability ## Footnote (Herlihy, 2020, p. 180)
72
The ___ ___ is the result of the numbers and types of ions, both positive (___) and negative (___), located inside the neuron. ## Footnote (Herlihy, 2020, p. 181)
resting state cations anions ## Footnote (Herlihy, 2020, p. 181)
73
What are pumped into negative cells by adenosine triphosphate (ATP)-driven pumps in the cell membrane? ## Footnote (Herlihy, 2020, p. 181)
Ions ## Footnote (Herlihy, 2020, p. 181)
74
The chief intracellular cation is ___ (___). In the resting state, however, some of the ___ (___) ions leak out of the cell, taking with them the positive charge. The lost positive charge and the excess anions trapped in the cell make the inside of the cell negative (−90 mv). ## Footnote (Herlihy, 2020, p. 181)
potassium (K+) potassium (K+) ## Footnote (Herlihy, 2020, p. 181)
75
It is the outward leak of potassium (K+) that is responsible for the ___ ___ ___. ## Footnote (Herlihy, 2020, p. 181)
resting membrane potential ## Footnote (Herlihy, 2020, p. 181)
76
When the neuron is stimulated, the permeability of the neuronal membrane changes in a way that allows ___ ___ (___) to diffuse rapidly across the membrane into the cell, carrying with it a positive (+) charge. Thus, it is the rapid inward diffusion of ___ ___ (___) that causes ___. ## Footnote (Herlihy, 2020, p. 181)
sodium ions (**Na+**) sodium ions (**Na+**), depolarization ## Footnote (Herlihy, 2020, p. 181)
77
Soon after the cell depolarizes, the neuronal membrane undergoes a second change. The change in the membrane permeability does two things: (1) it stops additional diffusion of ___ (___) into the cell, and (2) it allows ___ (___) to rapidly diffuse out of the cell. The outward diffusion of ___ (___) decreases the positive charge from the inside of the cell, leaving behind the negatively charged anions. Thus, the outward movement of ___ (___) causes repolarization and a return to the resting state. Eventually, membrane pumps restore intracellular ion concentrations; ___ (___) is pumped out of the cell, while ___ (___) is pumped into the cell. ## Footnote (Herlihy, 2020, p. 181)
sodium (**Na+**), potassium (**K+**) potassium (**K+**) potassium (**K+**) sodium (**Na+**) potassium (**K+**) ## Footnote (Herlihy, 2020, p. 181)
78
The ___ phase of the nerve impulse is not caused by the active transport pumps. ## Footnote (Herlihy, 2020, p. 181)
repolarizing ## Footnote (Herlihy, 2020, p. 181)
79
What is caused by the rapid outward diffusion of potassium (K+)? ## Footnote (Herlihy, 2020, p. 181)
Repolarization ## Footnote (Herlihy, 2020, p. 181)
80
The Ionic Basis of the Nerve Impulse ## Footnote (Herlihy, 2020, p. 182)
## Footnote (Herlihy, 2020, p. 182)
81
To convey information, a nerve impulse (action potential) must move the length of the neuron, from the ___ ___ to the ___ ___. Nerve impulse 2 then ___ the next segment of the membrane at point C, causing the formation of nerve impulse three (NI-3). ## Footnote (Herlihy, 2020, p. 181)
cell body, axon terminal depolarizes ## Footnote (Herlihy, 2020, p. 181)
82
Because of the ability of each nerve impulse to depolarize the adjacent membrane, the nerve impulse moves toward the axon terminal much like a ___. ## Footnote (Herlihy, 2020, p. 181)
wave ## Footnote (Herlihy, 2020, p. 181)
83
The height or ___ of each nerve impulse along the axon is the same. This is important because it ensures that the nerve impulse does not weaken as it travels the length of a long axon. ## Footnote (Herlihy, 2020, p. 181)
amplitude ## Footnote (Herlihy, 2020, p. 181)
84
Nerve Impulse Moving From the Cell Body to the Axon Terminals ## Footnote (Herlihy, 2020, p. 183)
## Footnote (Herlihy, 2020, p. 183)
85
What increases the movement of the nerve impulse along the axonal membrane? ## Footnote (Herlihy, 2020, p. 181)
Myelination ## Footnote (Herlihy, 2020, p. 181)
86
The axons of most nerve fibers are wrapped in myelin, a fatty material. At the ___ of ___, the axonal membrane is bare or unmyelinated. The nerve impulse arrives at the axon from the cell body but cannot develop on any part of the membrane covered with myelin. The nerve impulse can, however, develop at the ___ of ___, the bare axonal membrane. Thus, in a myelinated fiber, the nerve impulse jumps from node to node, much like a kangaroo, to the end of the axon. This “jumping” from node to node is called ___ ___ (from the Latin word saltare, meaning “to leap”). ## Footnote (Herlihy, 2020, p. 181)
nodes of Ranvier nodes of Ranvier saltatory conduction ## Footnote (Herlihy, 2020, p. 181)
87
___ ___ increases the speed with which the nerve impulse travels along the nerve fiber. For this reason, myelinated fibers are considered fast-conducting nerve fibers. ## Footnote (Herlihy, 2020, p. 181)
Saltatory conduction ## Footnote (Herlihy, 2020, p. 181)
88
## Footnote (Herlihy, 2020, p. 184)
## Footnote (Herlihy, 2020, p. 184)
89
The nerve impulse travels the length of the axon. However, the signal does not jump from one neuron to the next. A ___ helps information move chemically from one neuron to the next. ## Footnote (Herlihy, 2020, p. 182)
synapse ## Footnote (Herlihy, 2020, p. 182)
90
What is a space much like the neuromuscular junction? ## Footnote (Herlihy, 2020, p. 182)
Synaptic Cleft ## Footnote (Herlihy, 2020, p. 182)
91
What exists because the axon terminal of neuron A (presynaptic neuron) does not physically touch the dendrite of neuron B (postsynaptic neuron)? ## Footnote (Herlihy, 2020, p. 182)
Synaptic Cleft ## Footnote (Herlihy, 2020, p. 182)
92
The dendrite of neuron B contains ___ ___. ## Footnote (Herlihy, 2020, p. 182)
receptor sites ## Footnote (Herlihy, 2020, p. 182)
93
___ ___ are places on the membrane to which the neurotransmitters bind. For example, acetylcholine (ACh) binds to the ___ on dendrite B. ## Footnote (Herlihy, 2020, pp. 182, 183)
Receptor sites receptors ## Footnote (Herlihy, 2020, pp. 182, 183)
94
Each ___ ___ has a specific shape and accepts only those neurotransmitters that “fit” its shape. ## Footnote (Herlihy, 2020, p. 183)
receptor site ## Footnote (Herlihy, 2020, p. 183)
95
The axon terminal of neuron A contains thousands of tiny vesicles that store chemical substances called ___. ## Footnote (Herlihy, 2020, p. 183)
neurotransmitters ## Footnote (Herlihy, 2020, p. 183)
96
The most common neurotransmitters are ___ (___) and ___ (___). Other central nervous system (CNS) transmitters include epinephrine, serotonin, glutamate, dopamine, gamma-aminobutyric acid (GABA), and endorphins. ## Footnote (Herlihy, 2020, p. 183)
acetylcholine (**ACh**) norepinephrine (**NE**) ## Footnote (Herlihy, 2020, p. 183)
97
___ are substances that terminate the activity of the neurotransmitters when they have completed their task. For example, the neurotransmitter acetylcholine (ACh) is terminated by acetylcholinesterase. ## Footnote (Herlihy, 2020, p. 183)
Inactivators ## Footnote (Herlihy, 2020, p. 183)
98
___ is an enzyme located in the same area as the receptor sites on neuron B. Once acetylcholine (ACh) has completed its task, it is inactivated by ___. ## Footnote (Herlihy, 2020, p. 183)
Acetylcholinesterase acetylcholinesterase ## Footnote (Herlihy, 2020, p. 183)
99
The following details the events at the synapse: 1. The nerve impulse travels along neuron A to its ___ ___. 2. The nerve impulse causes the ___ to fuse with the membrane of the ___ ___. The ___ open and release the neurotransmitter into the synaptic cleft. 3. The neurotransmitter diffuses across the synaptic cleft and binds to the ___ ___. The binding of the neurotransmitter to the ___ ___ causes a change in the membrane potential of the dendrite of neuron B, thereby developing a nerve impulse. The neurotransmitter then vacates the ___ and is degraded. 4. Electrical information travels toward the ___ ___ and ___ of neuron B. Information from neuron A has been transmitted chemically to neuron B. ## Footnote (Herlihy, 2020, p. 184)
axon terminal vesicles, axon terminal vesicles receptor site receptor site receptor cell body, axon ## Footnote (Herlihy, 2020, p. 184)
100
Steps in the Transfer of Information Across the Synapse ## Footnote (Herlihy, 2020, p. 185)
## Footnote (Herlihy, 2020, p. 185)
101
The brain is located in the ___ cavity. ## Footnote (Herlihy, 2020, p. 185)
cranial ## Footnote (Herlihy, 2020, p. 185)
102
What is a pinkish-gray, delicate structure with a soft consistency? ## Footnote (Herlihy, 2020, p. 185)
Brain ## Footnote (Herlihy, 2020, p. 185)
103
The surface of the ___ appears bumpy, much like a walnut. The “boss of it all” weighs only ___ lb! ## Footnote (Herlihy, 2020, p. 185)
brain 3 ## Footnote (Herlihy, 2020, p. 185)
104
Despite the fact that the brain weighs only 2% of the total body weight, it requires ___% of the body’s oxygen supply. ## Footnote (Herlihy, 2020, p. 185)
20 ## Footnote (Herlihy, 2020, p. 185)
105
What is the primary source of energy for the brain? ## Footnote (Herlihy, 2020, p. 185)
Glucose ## Footnote (Herlihy, 2020, p. 185)
106
When blood glucose levels get very low (___), the person experiences mental confusion, dizziness, seizures, loss of consciousness, and death. No wonder that many of the body’s hormones are concerned with making glucose available to the brain. ## Footnote (Herlihy, 2020, pp. 185, 186)
hypoglycemia ## Footnote (Herlihy, 2020, pp. 185, 186)
107
Until recently, it was believed that each part of the brain had a specific function and if that part of the brain was damaged, its function was forever lost. In other words, the brain was anatomically and functionally fixed. Historically, the idea of an unchangeable brain gradually gave way to a different view, called ___, in response to the observation that the brain does change in response to different environmental cues and thought processes. For example, in persons blind since birth, the ___ ___ of the brain, which is normally concerned with vision, becomes populated with neurons that are involved in hearing. The ___ effect: if the occipital lobe can not see, it will hear. ## Footnote (Herlihy, 2020, p. 186)
neuroplasticity occipital lobe neuroplastic, occipital lobe ## Footnote (Herlihy, 2020, p. 186)
108
There is both good news and bad news about ___. Consider the person who has sustained a brain injury and is unable to walk. If motor pathways for walking are damaged, other pathways may be recruited and trained to restore the ability to walk. There are many medical examples of beneficial ___ effects. ## Footnote (Herlihy, 2020, p. 186)
neuroplasticity neuropathic ## Footnote (Herlihy, 2020, p. 186)
109
___ also has its downside, as noted by those who study the effects of hard pornography, violence, and negative thought patterns on brain function. ## Footnote (Herlihy, 2020, p. 186)
Neuroplasticity ## Footnote (Herlihy, 2020, p. 186)
110
In brief, ___ says this—what we think and sense changes our brains. ## Footnote (Herlihy, 2020, p. 186)
neuroplasticity ## Footnote (Herlihy, 2020, p. 186)
111
The brain is divided into four major areas: the ___, the ___, the ___ ___, and the ___. ## Footnote (Herlihy, 2020, p. 186)
cerebrum diencephalon brain stem cerebellum ## Footnote (Herlihy, 2020, p. 186)
112
Four Major Areas of the Brain ## Footnote (Herlihy, 2020, p. 186)
## Footnote (Herlihy, 2020, p. 186)
113
What is the largest part of the brain? ## Footnote (Herlihy, 2020, p. 186)
Cerebrum ## Footnote (Herlihy, 2020, p. 186)
114
What is divided into the right and left hemispheres? ## Footnote (Herlihy, 2020, p. 186)
Cerebrum ## Footnote (Herlihy, 2020, p. 186)
115
The cerebral hemispheres are joined together by bands of white matter that form a large fiber tract called the ___ ___. ## Footnote (Herlihy, 2020, p. 186)
corpus callosum ## Footnote (Herlihy, 2020, p. 186)
116
What allows the right and left sides of the brain to communicate with each other? ## Footnote (Herlihy, 2020, p. 186)
Corpus Callosum ## Footnote (Herlihy, 2020, p. 186)
117
Each cerebral hemisphere has four major lobes: ___, ___, ___, and ___. These four lobes are named for the overlying cranial bones. ## Footnote (Herlihy, 2020, p. 186)
frontal parietal temporal occipital ## Footnote (Herlihy, 2020, p. 186)
118
The cerebrum contains both ___ and ___ matter. ## Footnote (Herlihy, 2020, p. 186)
gray white ## Footnote (Herlihy, 2020, p. 186)
119
A thin layer of gray matter, called the ___ ___, forms the outermost portion of the cerebrum. ## Footnote (Herlihy, 2020, p. 186)
cerebral cortex ## Footnote (Herlihy, 2020, p. 186)
120
The cerebral cortex is composed primarily of ___ ___ and ___ and is therefore gray. ## Footnote (Herlihy, 2020, p. 186)
cell bodies interneurons ## Footnote (Herlihy, 2020, p. 186)
121
The gray matter of the ___ ___ allows us to perform higher mental tasks such as learning, reasoning, language, and memory. ## Footnote (Herlihy, 2020, p. 186)
cerebral cortex ## Footnote (Herlihy, 2020, p. 186)
122
The bulk of the cerebrum is composed of ___ ___ located directly below the cortex. ## Footnote (Herlihy, 2020, p. 186)
white matter ## Footnote (Herlihy, 2020, p. 186)
123
The white matter is composed primarily of ___ ___ that form connections between the parts of the brain and spinal cord. ## Footnote (Herlihy, 2020, p. 186)
myelinated axons ## Footnote (Herlihy, 2020, p. 186)
124
Scattered throughout the white matter are patches of gray matter called ___. ## Footnote (Herlihy, 2020, p. 186)
nuclei ## Footnote (Herlihy, 2020, p. 186)
125
The bumpy surface of the cerebrum has numerous markings with special names. The surface of the cerebrum is folded into elevations that resemble speed bumps on a road. The elevations are called ___, or ___. This extensive folding arrangement increases the amount of cerebral cortex, or thinking tissue. ## Footnote (Herlihy, 2020, p. 188)
convolutions gyrus ## Footnote (Herlihy, 2020, p. 188)
126
It is thought that intelligence is related to the amount of cerebral cortex and therefore to the numbers of ___ or ___. ## Footnote (Herlihy, 2020, p. 188)
convolutions gyrus ## Footnote (Herlihy, 2020, p. 188)
127
The greater the numbers of ___ in the brain, the more intelligent the species. ## Footnote (Herlihy, 2020, p. 188)
convolutions ## Footnote (Herlihy, 2020, p. 188)
128
Gyri are separated by grooves called ___. ## Footnote (Herlihy, 2020, p. 188)
sulcus ## Footnote (Herlihy, 2020, p. 188)
129
A deep sulcus is called a ___. ## Footnote (Herlihy, 2020, p. 188)
fissure ## Footnote (Herlihy, 2020, p. 188)
130
___ and ___ separate the cerebrum into lobes. ## Footnote (Herlihy, 2020, p. 188)
Sulci fissures ## Footnote (Herlihy, 2020, p. 188)
131
The ___ ___ separates the frontal lobe from the parietal lobes. ## Footnote (Herlihy, 2020, p. 188)
central sulcus ## Footnote (Herlihy, 2020, p. 188)
132
The ___ ___ is an important landmark, separating the precentral and postcentral gyri. ## Footnote (Herlihy, 2020, p. 188)
central sulcus ## Footnote (Herlihy, 2020, p. 188)
133
The ___ ___ is located in the frontal lobe, directly in front of the central sulcus, and the ___ ___ is located in the parietal lobe, directly behind the central sulcus. ## Footnote (Herlihy, 2020, p. 188)
precentral gyrus postcentral gyrus ## Footnote (Herlihy, 2020, p. 188)
134
The ___ ___ separates the temporal lobe from the frontal and the parietal lobes. ## Footnote (Herlihy, 2020, p. 188)
lateral sulcus ## Footnote (Herlihy, 2020, p. 188)
135
The ___ ___ separates the left and right cerebral hemispheres. ## Footnote (Herlihy, 2020, p. 188)
longitudinal fissure ## Footnote (Herlihy, 2020, p. 188)
136
The ___ ___ is located in the front of the cranium under the frontal bone. ## Footnote (Herlihy, 2020, p. 188)
frontal lobe ## Footnote (Herlihy, 2020, p. 188)
137
The ___ ___ plays a key role in voluntary motor activity, personality development, emotional and behavioural expression, and performance of high-level tasks such as learning, thinking, and making plans; these are sometimes called ___ ___. ## Footnote (Herlihy, 2020, p. 188)
frontal lobe executive functions ## Footnote (Herlihy, 2020, p. 188)
138
The frontal lobe contains the ___ ___ ___ (___). ## Footnote (Herlihy, 2020, p. 188)
primary motor area (**cortex**) ## Footnote (Herlihy, 2020, p. 188)
139
Nerve impulses that originate in the ___ ___ ___ control voluntary muscle movement. ## Footnote (Herlihy, 2020, p. 188)
primary motor cortex ## Footnote (Herlihy, 2020, p. 188)
140
When you decide to move your leg, the nerve impulse originates in the ___ ___, or primary motor cortex, of the ___ ___. The axons of these motor neurons form the voluntary motor tracts that descend the spinal cord. ## Footnote (Herlihy, 2020, p. 188)
precentral gyrus frontal lobe ## Footnote (Herlihy, 2020, p. 188)
141
The function of the ___ ___ of the frontal lobe is illustrated by a homunculus, meaning “little man”. The homunculus represents the amount of brain tissue that corresponds to a function of a particular body part. ## Footnote (Herlihy, 2020, p. 188)
precentral gyrus ## Footnote (Herlihy, 2020, p. 188)
142
The homunculus shows two important points; each part of the body is controlled by a specific area of the ___ ___ of the precentral gyrus, and the complicated nature of certain movements requires large amounts of ___ ___. For example, the movements of the hand are much more delicate and complicated than the movements of the foot. Therefore, the amount of ___ ___ devoted to hand and finger movement is much greater than the amount devoted to foot and toe movement. Consequently, the homunculus has huge hands and small feet. Note also the amount of ___ ___ required to run your mouth. ## Footnote (Herlihy, 2020, p. 188)
cerebral cortex, brain tissue brain tissue brain tissue ## Footnote (Herlihy, 2020, p. 188)
143
In addition to its role in voluntary motor activity, the frontal lobe plays a key role in ___ ___. ## Footnote (Herlihy, 2020, p. 188)
motor speech ## Footnote (Herlihy, 2020, p. 188)
144
What refers to the movements of the mouth and tongue necessary for the formation of words to express your thoughts? ## Footnote (Herlihy, 2020, p. 188)
Motor Speech ## Footnote (Herlihy, 2020, p. 188)
145
The part of the frontal lobe concerned with motor speech is called ___ area. In most persons, ___ area is in the left hemisphere. ## Footnote (Herlihy, 2020, p. 188)
Broca’s Broca’s ## Footnote (Herlihy, 2020, p. 188)
146
If the Bronca's area is damaged, as commonly happens with a stroke or brain attack, the person develops a type of ___. The person knows what he or she wants to say but cannot say it. ## Footnote (Herlihy, 2020, p. 188)
aphasia ## Footnote (Herlihy, 2020, p. 188)
147
Just above Broca’s area is an area called the ___ ___ ___. It controls voluntary movements of the eyes and the eyelids. Your ability to scan this paragraph is a function of this area. ## Footnote (Herlihy, 2020, p. 188)
frontal eye field ## Footnote (Herlihy, 2020, p. 188)
148
The ___ ___ is located posterior to the central sulcus. ## Footnote (Herlihy, 2020, p. 189)
parietal lobe ## Footnote (Herlihy, 2020, p. 189)
149
The parietal lobe, particularly the ___ ___, is primarily concerned with receiving general sensory information from the body. ## Footnote (Herlihy, 2020, p. 189)
postcentral gyrus ## Footnote (Herlihy, 2020, p. 189)
150
Because it receives sensations from the body, the parietal lobe is called the ___ ___ area. This area receives information primarily from the skin and muscles and allows you to experience the sensations of temperature, pain, light touch, and proprioception (a sense of where your body is). ## Footnote (Herlihy, 2020, p. 189)
primary somatosensory ## Footnote (Herlihy, 2020, p. 189)
151
The ___ ___ is also concerned with reading, speech, and taste. ## Footnote (Herlihy, 2020, p. 189)
parietal lobe ## Footnote (Herlihy, 2020, p. 189)
152
Like the motor homunculus in the precentral gyrus, a sensory homunculus can be drawn along the ___ ___. ## Footnote (Herlihy, 2020, p. 189)
postcentral gyrus ## Footnote (Herlihy, 2020, p. 189)
153
The ___ ___ is located in the frontal lobe and is the primary motor area. ## Footnote (Herlihy, 2020, p. 189)
precentral gyrus ## Footnote (Herlihy, 2020, p. 189)
154
The ___ ___ is located in the parietal lobe and is the primary somatosensory area. ## Footnote (Herlihy, 2020, p. 189)
postcentral gyrus ## Footnote (Herlihy, 2020, p. 189)
155
Motor Area of the Frontal Lobe (Precentral Gyrus), Illustrated with a Homunculus ## Footnote (Herlihy, 2020, p. 190)
## Footnote (Herlihy, 2020, p. 190)
156
The ___ ___ is located inferior to the lateral fissure in an area just above the ear. ## Footnote (Herlihy, 2020, p. 189)
temporal lobe ## Footnote (Herlihy, 2020, p. 189)
157
The temporal lobe contains an area called the ___ ___ ___. It receives sensory information from the ears and allows you to hear. ## Footnote (Herlihy, 2020, p. 189)
primary auditory cortex ## Footnote (Herlihy, 2020, p. 189)
158
Damage to the ___ ___ causes cortical deafness. ## Footnote (Herlihy, 2020, p. 189)
temporal lobe ## Footnote (Herlihy, 2020, p. 189)
159
The temporal lobe also receives sensory information from the nose; this area is called the ___ area, the area that senses smell. ## Footnote (Herlihy, 2020, p. 189)
olfactory ## Footnote (Herlihy, 2020, p. 189)
160
Sensory information from the taste buds in the tongue is interpreted in both the ___ and ___ lobes. ## Footnote (Herlihy, 2020, p. 189)
temporal parietal ## Footnote (Herlihy, 2020, p. 189)
161
A broad region called ___ area is located in the parietal and temporal lobes; it is concerned with the translation of thought into words. Damage to this area, as occurs with chronic alcohol abuse, can result in severe deficits in language comprehension. ## Footnote (Herlihy, 2020, p. 189)
Wernicke’s ## Footnote (Herlihy, 2020, p. 189)
162
The ___ ___ is located in the posterior part of the cerebrum, underlying the occipital bone. ## Footnote (Herlihy, 2020, p. 189)
occipital lobe ## Footnote (Herlihy, 2020, p. 189)
163
The occipital lobe contains the ___ ___. ## Footnote (Herlihy, 2020, p. 189)
visual cortex ## Footnote (Herlihy, 2020, p. 189)
164
Sensory fibers from the eye send information to the ___ ___ ___ of the occipital lobe, where it is interpreted as sight. ## Footnote (Herlihy, 2020, p. 189)
primary visual cortex ## Footnote (Herlihy, 2020, p. 189)
165
The occipital lobe is also concerned with many visual reflexes and vision-related functions such as reading (through the ___ ___ area). ## Footnote (Herlihy, 2020, p. 189)
visual association ## Footnote (Herlihy, 2020, p. 189)
166
Damage to the primary visual cortex of the ___ ___ causes cortical blindness. ## Footnote (Herlihy, 2020, p. 189)
occipital lobe ## Footnote (Herlihy, 2020, p. 189)
167
Although specific functions can be attributed to each cerebral lobe, most functions depend on more than one area of the brain. The ___ area, for example, is located in an area that includes the temporal, parietal, and occipital lobes. In most people, the ___ area is located in the left hemisphere. ## Footnote (Herlihy, 2020, p. 189)
speech speech ## Footnote (Herlihy, 2020, p. 189)
168
The ___ area allows you to understand words, whether written or spoken. When you have gathered your thoughts, ___ area in the frontal lobe directs the muscles of the larynx, tongue, cheeks, and lips to speak. ## Footnote (Herlihy, 2020, p. 189)
speech Broca’s ## Footnote (Herlihy, 2020, p. 189)
169
Other functions require input from more than one brain structure. The ability to read, for example, requires interpretation of the visual information by the ___ ___. It also requires understanding of the words and the coordination of the eyes as they scan the page. A vast amount of brain tissue beyond the ___ ___ is involved in vision and vision-related functions such as reading. ## Footnote (Herlihy, 2020, p. 190)
occipital lobe occipital lobe ## Footnote (Herlihy, 2020, p. 190)
170
Large areas of the cerebral cortex are called ___ areas. These areas are concerned primarily with analyzing, interpreting, and integrating information. For example, a small area of the temporal lobe, called the ___ ___ ___, receives sensory information from the ear. The surrounding area, called the ___ ___ area, uses a large store of knowledge and experience to identify and give meaning to the sound. In other words, the ___ ___ ___ hears the noise, and the ___ ___ area interprets the noise. The brain contains receiving and ___ areas for other sensations as well (e.g., visual ___ area, somatosensory ___ area). ## Footnote (Herlihy, 2020, pp. 190, 191)
association primary auditory cortex auditory association primary auditory cortex auditory association association x 3 ## Footnote (Herlihy, 2020, pp. 190, 191)
171
Scattered throughout the cerebral white matter are patches of gray matter called ___ ___ (sometimes called ___ ___). ## Footnote (Herlihy, 2020, p. 191)
basal nuclei basal ganglia ## Footnote (Herlihy, 2020, p. 191)
172
The ___ ___ help regulate body movement and facial expression. ## Footnote (Herlihy, 2020, p. 191)
basal nuclei ## Footnote (Herlihy, 2020, p. 191)
173
The neurotransmitter ___ is largely responsible for the activity of the basal nuclei. ## Footnote (Herlihy, 2020, p. 191)
dopamine ## Footnote (Herlihy, 2020, p. 191)
174
A deficiency of dopamine within the basal nuclei is called ___ disease, a movement disorder or ___. ## Footnote (Herlihy, 2020, p. 191)
Parkinson dyskinesia ## Footnote (Herlihy, 2020, p. 191)
175
Because of the characteristic shaking (tremors), ___ disease is sometimes called shaking palsy. ___-producing drugs are usually prescribed to treat this condition. ## Footnote (Herlihy, 2020, p. 191)
Parkinson Dopamine ## Footnote (Herlihy, 2020, p. 191)
176
A) Lobes of the Cerebrum B) Functional Areas of the Cerebrum ## Footnote (Herlihy, 2020, p. 187)
## Footnote (Herlihy, 2020, p. 187)
177
The ___ is the second main area of the brain. It is located beneath the cerebrum and above the brain stem. ## Footnote (Herlihy, 2020, p. 191)
Diencephalon ## Footnote (Herlihy, 2020, p. 191)
178
The diencephalon includes the ___ and the ___. ## Footnote (Herlihy, 2020, p. 191)
thalamus hypothalamus ## Footnote (Herlihy, 2020, p. 191)
179
What serves as a relay station for most of the sensory fibers traveling from the lower brain and spinal cord region to the sensory areas of the cerebrum? ## Footnote (Herlihy, 2020, p. 191)
Thalamus ## Footnote (Herlihy, 2020, p. 191)
180
The ___ sorts out the sensory information, gives us a hint of the sensation we are to experience, and then directs the information to the specific cerebral areas for more precise interpretation. For example, pain fibers coming from the body to the brain pass through the ___. At the level of the ___, we become aware of pain, but we are not yet aware of the type of pain or the exact location of the pain. Fibers that transmit pain information from the ___ to the cerebral cortex provide us with that additional information. ## Footnote (Herlihy, 2020, p. 191)
thalamus thalamus thalamus thalamus ## Footnote (Herlihy, 2020, p. 191)
181
The ___ is the second structure in the diencephalon. It is situated directly below the thalamus and helps regulate many body processes, including body temperature (thermostat), water balance, and metabolism. ## Footnote (Herlihy, 2020, p. 191)
hypothalamus ## Footnote (Herlihy, 2020, p. 191)
182
Because the ___ helps regulate the function of the autonomic (involuntary) nerves, it exerts an effect on heart rate, blood pressure, and respiration. ## Footnote (Herlihy, 2020, p. 191)
hypothalamus ## Footnote (Herlihy, 2020, p. 191)
183
Located under the hypothalamus is the ___ ___. ## Footnote (Herlihy, 2020, p. 191)
pituitary gland ## Footnote (Herlihy, 2020, p. 191)
184
The ___ ___ directly or indirectly affects almost every hormone in the body. ## Footnote (Herlihy, 2020, p. 191)
pituitary gland ## Footnote (Herlihy, 2020, p. 191)
185
Because the ___ controls pituitary function, the widespread effects of the ___ are obvious. ## Footnote (Herlihy, 2020, p. 191)
hypothalamus hypothalamus ## Footnote (Herlihy, 2020, p. 191)
186
The ___ ___ connects the spinal cord with higher brain structures. ## Footnote (Herlihy, 2020, p. 191)
brain stem ## Footnote (Herlihy, 2020, p. 191)
187
The brain stem is composed of the ___, ___, and ___ ___. ## Footnote (Herlihy, 2020, p. 191)
midbrain pons medulla oblongata ## Footnote (Herlihy, 2020, p. 191)
188
The ___ matter of the brain stem includes tracts that relay both sensory and motor information to and from the cerebrum. ## Footnote (Herlihy, 2020, p. 191)
white ## Footnote (Herlihy, 2020, p. 191)
189
Scattered throughout the white matter of the brain stem are patches of gray matter called ___. These ___ exert profound effects on functions such as blood pressure and respiration. ## Footnote (Herlihy, 2020, p. 191)
nuclei nuclei ## Footnote (Herlihy, 2020, p. 191)
190
The ___ extends from the lower diencephalon to the pons. Like the rest of the brain-stem structures, it relays ___ and ___ information. ## Footnote (Herlihy, 2020, p. 191)
midbrain sensory, motor ## Footnote (Herlihy, 2020, p. 191)
191
The midbrain contains ___ that function as reflex centers for vision and hearing. ## Footnote (Herlihy, 2020, p. 191)
nuclei ## Footnote (Herlihy, 2020, p. 191)
192
The ___ (bridge) extends from the midbrain to the medulla oblongata. ## Footnote (Herlihy, 2020, p. 191)
pons ## Footnote (Herlihy, 2020, p. 191)
193
What is composed primarily of tracts that act as a bridge for information traveling to and from several brain structures? ## Footnote (Herlihy, 2020, p. 191)
Pons ## Footnote (Herlihy, 2020, p. 191)
194
What plays an important role in the regulation of breathing rate and rhythm? ## Footnote (Herlihy, 2020, p. 191)
Pons ## Footnote (Herlihy, 2020, p. 191)
195
The ___ ___ connects the spinal cord with the pons. It acts as a relay for ___ and ___ information. ## Footnote (Herlihy, 2020, p. 191)
Medulla Oblongata sensory, motor ## Footnote (Herlihy, 2020, p. 191)
196
Several important ___ within the medulla control the vital functions: heart rate, blood pressure, and respiration. Because of its importance to these life-sustaining functions, the medulla oblongata is called the ___ ___. ## Footnote (Herlihy, 2020, p. 191)
nuclei vital center ## Footnote (Herlihy, 2020, p. 191)
197
The ___ ___ is sensitive to certain drugs, especially opioids such as morphine. An overdose of an opioid causes depression of the ___ ___ and death because the person stops breathing. This danger is the reason for assessing respiratory rate before giving a patient an opioid. ## Footnote (Herlihy, 2020, p. 191)
medulla oblongata medulla oblongata ## Footnote (Herlihy, 2020, p. 191)
198
The ___ ___ contains the vomiting center, or emetic center (emesis refers to vomiting). ## Footnote (Herlihy, 2020, p. 192)
medulla oblongata ## Footnote (Herlihy, 2020, p. 192)
199
The vomiting center can be activated directly or indirectly. Direct activation includes stimuli from the ___ ___ (fear), stimuli from sensory organs (distressing sights, bad odors, pain), and signals from the ___ ___ of the inner ear (spinning). Indirect stimulation of the vomiting center comes from the ___ ___ ___ (___) located in the floor of the fourth ventricle. The ___ ___ ___ (___) can be stimulated by emetogenic compounds, such as anticancer drugs and opioids. ## Footnote (Herlihy, 2020, p. 192)
cerebral cortex, equilibrium apparatus chemoreceptor trigger zone (**CTZ**) chemoreceptor trigger zone (**CTZ**) ## Footnote (Herlihy, 2020, p. 192)
200
Signals from the digestive tract, especially the stomach, travel via the vagus nerve to the ___ ___ ___ (___). The ___ ___ ___ (___), in turn, activates the vomiting center. ## Footnote (Herlihy, 2020, p. 192)
chemoreceptor trigger zone (**CTZ**) chemoreceptor trigger zone (**CTZ**) ## Footnote (Herlihy, 2020, p. 192)
201
___ agents can work on both the chemoreceptor trigger zone (CTZ) and medullary vomiting center to relieve nausea and vomiting. ## Footnote (Herlihy, 2020, p. 192)
Antiemetic ## Footnote (Herlihy, 2020, p. 192)
202
The pharmacologic management of vomiting is a common clinical problem. Another interesting point is that ___, which often precedes vomiting, is derived from the Greek word for “ship,” as in seasickness. ## Footnote (Herlihy, 2020, p. 192)
nausea ## Footnote (Herlihy, 2020, p. 192)
203
The ___, the fourth major area, is the structure that protrudes from under the occipital lobe. ## Footnote (Herlihy, 2020, p. 192)
cerebellum ## Footnote (Herlihy, 2020, p. 192)
204
Which structure has more than half the neurons in the entire brain? ## Footnote (Herlihy, 2020, p. 192)
Cerebellum ## Footnote (Herlihy, 2020, p. 192)
205
The interior of the cerebellum is composed largely of ___ tracts. Notice the appearance of the tracts; the cerebellum looks like a tree and is therefore called the ___ ___ or literally the “living tree.” ## Footnote (Herlihy, 2020, p. 192)
white arbor vitae ## Footnote (Herlihy, 2020, p. 192)
206
The cerebellum is connected to the brain stem by three pairs of cerebellar ___; these connections allow the cerebellum to receive, integrate, and deliver information to many parts of the brain and spinal cord. ## Footnote (Herlihy, 2020, p. 192)
peduncles ## Footnote (Herlihy, 2020, p. 192)
207
The ___ is concerned with the coordination of voluntary muscle activity and maintaining equilibrium and posture. ## Footnote (Herlihy, 2020, p. 192)
cerebellum ## Footnote (Herlihy, 2020, p. 192)
208
Damage to the ___ produces jerky muscle movements, staggering gait, and difficulty maintaining balance. ## Footnote (Herlihy, 2020, p. 192)
cerebellum ## Footnote (Herlihy, 2020, p. 192)
209
A person with ___ dysfunction may appear intoxicated. ## Footnote (Herlihy, 2020, p. 192)
cerebellum ## Footnote (Herlihy, 2020, p. 192)
210
The ___ normally coordinates skeletal muscle activity. To help diagnose ___ dysfunction, the physician may ask the person to touch the tip of his or her nose with a finger. In attempting to touch the nose, a patient with ___ dysfunction may overshoot, first to one side and then to the other. ## Footnote (Herlihy, 2020, p. 192)
cerebellum cerebellum cerebellum ## Footnote (Herlihy, 2020, p. 192)
211
The ___ plays an important role in the evaluation of sensory input. For example, the ___ allows a person to evaluate the texture of different fabrics without seeing the fabric. It also “times” events, thereby allowing the person to predict where a moving object will be in the next few seconds. For example, a basketball player has a keen sense of where the ball is and should be in the next dribble or two. And most of us can rhythmically drum our fingers on a desk—a task that is impaired in someone with ___ dysfunction ## Footnote (Herlihy, 2020, pp. 192, 193)
cerebellum cerebellum cerebellum ## Footnote (Herlihy, 2020, pp. 192, 193)
212
## Footnote (Herlihy, 2020, p. 192)
## Footnote (Herlihy, 2020, p. 192)
213
Three important structures are not confined to any of the four divisions of the brain because they “overlap” several areas. These structures are the ___ system, the ___ system, and the ____ areas. ## Footnote (Herlihy, 2020, p. 193)
limbic reticular memory ## Footnote (Herlihy, 2020, p. 193)
214
Parts of the cerebrum and the diencephalon form a wishbone-shaped group of structures called the ___ system. ## Footnote (Herlihy, 2020, p. 193)
limbic ## Footnote (Herlihy, 2020, p. 193)
215
The ___ system functions in emotional states and behaviour. For example, when the ___ system is stimulated by electrodes, states of extreme pleasure or rage can be induced. Because of these responses, the ___ system is called the emotional brain. ## Footnote (Herlihy, 2020, p. 193)
limbic limbic limbic ## Footnote (Herlihy, 2020, p. 193)
216
Extending through the entire brain stem and diencephalon, with numerous connections to the cerebral cortex, is a special mass of gray matter called the ___ ___. ## Footnote (Herlihy, 2020, p. 193)
reticular formation ## Footnote (Herlihy, 2020, p. 193)
217
The ___ ___ has both a sensory and motor function. Its primary sensory function is to alert the ___ ___ of incoming sensory information. Its primary motor function is to regulate ___ ___, the mild state of muscle contraction while the body is at rest. ## Footnote (Herlihy, 2020, p. 193)
reticular formation cerebral cortex muscle tone ## Footnote (Herlihy, 2020, p. 193)
218
Other nuclei within the reticular formation include the ___ ___ (allow the eyes to track an object) and special groups of cells that rhythmically send signals to the muscles that control breathing and swallowing. ## Footnote (Herlihy, 2020, p. 193)
gaze centers ## Footnote (Herlihy, 2020, p. 193)
219
The reticular formation is also concerned with ___, the process whereby the brain learns to ignore repetitive background information. For example, a parent may ignore the background noise of children playing and horns honking, but responds immediately to a crying child. Similarly, while driving a car, you ignore much of the background visual information but are aware of traffic signals, nearby cars, and, hopefully, any oncoming vehicles. ## Footnote (Herlihy, 2020, p. 193)
habituation ## Footnote (Herlihy, 2020, p. 193)
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A portion of the reticular formation, the ___ ___ ___ (___) is concerned with the sleep–wake cycle. ## Footnote (Herlihy, 2020, p. 193)
reticular activating system (**RAS**) ## Footnote (Herlihy, 2020, p. 193)
221
Signals passing up to the cerebral cortex from the ___ ___ ___ (___) stimulate us, keeping us awake and tuned in. ## Footnote (Herlihy, 2020, p. 193)
reticular activating system (**RAS**) ## Footnote (Herlihy, 2020, p. 193)
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Diminished activation of the ___ ___ ___ (___) produces sleep. ## Footnote (Herlihy, 2020, p. 193)
reticular activating system (**RAS**) ## Footnote (Herlihy, 2020, p. 193)
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___ ___ ___ (___) depression induces a coma state. ## Footnote (Herlihy, 2020, p. 193)
reticular activating system (**RAS**) ## Footnote (Herlihy, 2020, p. 193)
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Coma is a hyporesponsive state with several stages, ranging from light to deep coma. In the lightest stages of coma, some reflexes are intact; the patient may respond to light, sound, touch, and painful stimuli. As the coma deepens, however, these reflexes are gradually lost, and the patient eventually becomes unresponsive to all stimuli. Many clinical conditions affect ___ ___ ___ (___) or awareness. As a clinician, you must be able to assess the patient’s ___ ___ ___ (___). ## Footnote (Herlihy, 2020, p. 193)
level of consciousness (**LOC**) level of consciousness (**LOC**) ## Footnote (Herlihy, 2020, p. 193)
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Our sleeping brains, however, are not less active during sleep, but active in a different way. In fact, the sleeping brain consumes as much ___ as does the waking brain. ## Footnote (Herlihy, 2020, p. 193)
oxygen ## Footnote (Herlihy, 2020, p. 193)
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The waking brain functions in a nonstop information-collecting mode. The sleeping brain ___ this information; it sifts through the massive amounts of information, keeping or discarding what it collected in the waking state. ## Footnote (Herlihy, 2020, pp. 193, 194)
edits ## Footnote (Herlihy, 2020, pp. 193, 194)
227
The ___ brain assigns meaning to the happenings of the day and prepares it for storage in long-term memory. To “___ on a problem” is to respect the ability of the ___ brain to figure it out and propose solutions. ## Footnote (Herlihy, 2020, p. 194)
sleeping sleep sleeping ## Footnote (Herlihy, 2020, p. 194)
228
To state that sleep is an absurdity also assumes that the body during sleep does not perform differently; it does. Physiology is altered. For instance, ___ ___ (___) secretion surges with sleep therefore affecting metabolism and stimulating proteins that promote immune function. ## Footnote (Herlihy, 2020, p. 194)
growth hormone (**GH**) ## Footnote (Herlihy, 2020, p. 194)
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Sleep is initiated by a rise in the secretion of ___, but there is still more to the initiation of sleep than ___ secretion. We also know that most Americans do not get enough sleep each night and that chronic sleep deprivation is linked to numerous health problems such as obesity, diabetes mellitus, hypertension, and heart disease. ## Footnote (Herlihy, 2020, p. 194)
melatonin melatonin ## Footnote (Herlihy, 2020, p. 194)
230
What refers to the easily reversible state characterized by diminished consciousness and lack of interaction with the environment? ## Footnote (Herlihy, 2020, p. 194)
Sleep ## Footnote (Herlihy, 2020, p. 194)
231
The two types of sleep are ___-___ ___ ___ (___) sleep and ___ ___ ___ (___) sleep. ## Footnote (Herlihy, 2020, p. 194)
non–rapid eye movement (**NREM**) rapid eye movement (**REM**) ## Footnote (Herlihy, 2020, p. 194)
232
The four stages of ___-___ ___ ___ (___) sleep progress from light to deep. In a typical 8-hour sleep period, a person regularly cycles through the various stages of sleep, descending from light to deep sleep and then ascending from deeper sleep to lighter sleep. ## Footnote (Herlihy, 2020, p. 194)
non–rapid eye movement (**NREM**) ## Footnote (Herlihy, 2020, p. 194)
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___ ___ ___ (___) sleep is characterized by fluctuating blood pressure, respiratory rate and rhythm, and pulse rate. ## Footnote (Herlihy, 2020, p. 194)
rapid eye movement (**REM**) ## Footnote (Herlihy, 2020, p. 194)
234
The most obvious characteristic of ___ ___ ___ (___) sleep is rapid eye movements, for which the sleep segment is named. ## Footnote (Herlihy, 2020, p. 194)
rapid eye movement (**REM**) ## Footnote (Herlihy, 2020, p. 194)
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Rapid eye movement (REM) sleep totals ___ to ___ minutes per night. ## Footnote (Herlihy, 2020, p. 194)
90 120 ## Footnote (Herlihy, 2020, p. 194)
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For unknown reasons, ___ ___ ___ (___) sleep deprivation is associated with mental and physical distress. ## Footnote (Herlihy, 2020, p. 194)
rapid eye movement (**REM**) ## Footnote (Herlihy, 2020, p. 194)
237
Most sedatives and central nervous system (CNS) depressants adversely affect ___ ___ ___ (___) sleep, perhaps accounting for that “hangover” feeling that often follows their use. ## Footnote (Herlihy, 2020, p. 194)
rapid eye movement (**REM**) ## Footnote (Herlihy, 2020, p. 194)
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In addition to the rapid eye movements, ___ ___ ___ (___) sleep is the sleep segment during which most dreaming occurs. ## Footnote (Herlihy, 2020, p. 194)
rapid eye movement (**REM**) ## Footnote (Herlihy, 2020, p. 194)
239
Whatever their meaning, ___ are nightly events and seem to contribute to the beneficial effects of a good night’s sleep. ## Footnote (Herlihy, 2020, p. 194)
dreams ## Footnote (Herlihy, 2020, p. 194)
240
___ is the ability to recall thoughts and images. Many areas of the brain are concerned with ___. ## Footnote (Herlihy, 2020, p. 194)
Memory memory ## Footnote (Herlihy, 2020, p. 194)
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There are three categories of memory: ___ memory, ___-___ memory, and ___-___ memory. ## Footnote (Herlihy, 2020, p. 194)
immediate short-term long-term ## Footnote (Herlihy, 2020, p. 194)
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___ memory lasts for a few seconds. An example of your ___ memory is your ability to remember the words in the first part of the sentence so that you can get the thought of the entire sentence. ## Footnote (Herlihy, 2020, p. 194)
Immediate immediate ## Footnote (Herlihy, 2020, p. 194)
243
___-___ memory lasts for a short period (seconds to a few hours). It allows you to recall bits of information, such as the price of those new jeans or a phone number that you looked up. ## Footnote (Herlihy, 2020, p. 194)
Short-term ## Footnote (Herlihy, 2020, p. 194)
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Unfortunately, cramming for exams falls into this category—___-___ memorization, 5-second retention, and then: BLANK. ## Footnote (Herlihy, 2020, p. 194)
short-term ## Footnote (Herlihy, 2020, p. 194)
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___-___ memory lasts much longer—years, decades, or a lifetime. If you continuously use the new address or phone number, you will enter that information into your ___-___ memory. The same effect is achieved when you study over a longer period. ## Footnote (Herlihy, 2020, p. 194)
Long-term long-term ## Footnote (Herlihy, 2020, p. 194)
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Another interesting point: although memory is important, ___ is also important. Imagine all the trivial information that you take in every second. Think of the many stones, trees, birds, street signs, and other things that you pass on your way to work. Persons who have difficulty in ___ trivia have a great deal of difficulty in comprehension and in remembering things that need to be remembered. ## Footnote (Herlihy, 2020, p. 194)
forgetting forgetting ## Footnote (Herlihy, 2020, p. 194)
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## Footnote (Herlihy, 2020, p. 189)
## Footnote (Herlihy, 2020, p. 189)
248
The tissue of the central nervous system (CNS) (brain and spinal cord) is very delicate. Injury to central nervous system (CNS) neuronal tissue cannot be repaired. Thus, the central nervous system (CNS) has an elaborate protective system that consists of four structures: ___, ___, ___ ___ (___), and the ___-___ barrier. ## Footnote (Herlihy, 2020, p. 195)
bone meninges cerebrospinal fluid (**CSF**) blood–brain ## Footnote (Herlihy, 2020, p. 195)
249
The central nervous system (CNS) is protected by bone. The brain is encased in the ___, and the spinal cord is encased in the ___ ___. ## Footnote (Herlihy, 2020, p. 195)
cranium vertebral column ## Footnote (Herlihy, 2020, p. 195)
250
Three layers of connective tissue surround the brain and spinal cord. These tissues are called the ___. ## Footnote (Herlihy, 2020, p. 195)
meninges ## Footnote (Herlihy, 2020, p. 195)
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The outermost layer is a thick, tough, connective tissue called the ___ ___, literally meaning “hard mother.” ## Footnote (Herlihy, 2020, p. 195)
dura mater ## Footnote (Herlihy, 2020, p. 195)
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Inside the skull, the dural membrane splits to form the ___ sinuses. These sinuses are filled with blood. ## Footnote (Herlihy, 2020, p. 195)
dural ## Footnote (Herlihy, 2020, p. 195)
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Beneath the dura mater is a small space called the ___ space. ## Footnote (Herlihy, 2020, p. 195)
subdural ## Footnote (Herlihy, 2020, p. 195)
254
The middle meningeal layer is the ___ ___ (meaning “spider-like”), so named because the membrane looks like a spider web. ## Footnote (Herlihy, 2020, p. 195)
arachnoid mater ## Footnote (Herlihy, 2020, p. 195)
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The ___ ___ is the innermost layer and literally means “soft or gentle mother.” ## Footnote (Herlihy, 2020, p. 195)
pia mater ## Footnote (Herlihy, 2020, p. 195)
256
The ___ ___ is a very thin membrane that contains many blood vessels and lies delicately over the brain and spinal cord. These blood vessels supply the brain with much of its blood. ## Footnote (Herlihy, 2020, p. 195)
pia mater ## Footnote (Herlihy, 2020, p. 195)
257
Between the arachnoid layer and the pia mater is a space called the ___ space . A fluid called the ___ ___ (___) circulates within this space and forms a cushion around the brain and spinal cord. If the head is jarred suddenly, the brain first bumps into this soft cushion of fluid. ## Footnote (Herlihy, 2020, p. 195)
subarachnoid cerebrospinal fluid (**CSF**) ## Footnote (Herlihy, 2020, p. 195)
258
Specialized projections of the arachnoid membrane, called the ___ ___, protrude up into the blood-filled dural sinuses and are involved in the drainage of the cerebrospinal fluid (CSF). ## Footnote (Herlihy, 2020, p. 195)
arachnoid villi ## Footnote (Herlihy, 2020, p. 195)
259
The ___ form a brain PAD (noting that the brain is closer to pia, the softer mother). ## Footnote (Herlihy, 2020, p. 195)
meninges ## Footnote (Herlihy, 2020, p. 195)
260
## Footnote (Herlihy, 2020, p. 195)
## Footnote (Herlihy, 2020, p. 195)
261
The meninges can become inflamed or infected causing ___. ## Footnote (Herlihy, 2020, p. 195)
meningitis ## Footnote (Herlihy, 2020, p. 195)
262
What is serious because the infection can spread to the brain, sometimes causing serious, irreversible brain damage? ## Footnote (Herlihy, 2020, p. 195)
Meningitis ## Footnote (Herlihy, 2020, p. 195)
263
The bacterial or viral organism causing the meningitis can be found in the ___ ___ (___) obtained by lumbar puncture. ## Footnote (Herlihy, 2020, p. 195)
cerebrospinal fluid (**CSF**) ## Footnote (Herlihy, 2020, p. 195)
264
Three Layers of Meninges ## Footnote (Herlihy, 2020, p. 196)
## Footnote (Herlihy, 2020, p. 196)
265
The ___ ___ (___) forms a third protective layer of the central nervous system (CNS). ## Footnote (Herlihy, 2020, p. 195)
cerebrospinal fluid (**CSF**) ## Footnote (Herlihy, 2020, p. 195)
266
What is formed from the blood within the brain? ## Footnote (Herlihy, 2020, p. 195)
Cerebrospinal Fluid (CSF) ## Footnote (Herlihy, 2020, p. 195)
267
What is the clear fluid that looks like clear soda and is similar in composition to plasma? ## Footnote (Herlihy, 2020, p. 195)
Cerebrospinal Fluid (CSF) ## Footnote (Herlihy, 2020, p. 195)
268
The cerebrospinal fluid (CSF) is composed of water, ___, protein, and several ions, especially ___ (___) and ___ (___). ## Footnote (Herlihy, 2020, p. 195)
glucose sodium (**Na+**) chloride (**Cl −**) ## Footnote (Herlihy, 2020, p. 195)
269
An adult circulates about ___ mL of cerebrospinal fluid (CSF); ___ mL is formed every 24 hours, so cerebrospinal fluid (CSF) is replaced every ___ hours. ## Footnote (Herlihy, 2020, p. 195)
130 500 8 ## Footnote (Herlihy, 2020, p. 195)
270
In addition to its protective function, cerebrospinal fluid (CSF) also delivers nutrients to the ___ ___ ___ (___) and removes metabolic waste. ## Footnote (Herlihy, 2020, p. 195)
central nervous system (**CNS**) ## Footnote (Herlihy, 2020, p. 195)
271
Interestingly, the removal of metabolic waste from the central nercous system (CNS) by ___ ___ ___ (___) increases significantly during sleep. ## Footnote (Herlihy, 2020, p. 195)
cerebrospinal fluid (**CSF**) ## Footnote (Herlihy, 2020, p. 195)
272
Cerebrospinal fluid (CSF) is formed within the ventricles of the brain by a structure called the ___ ___. The four ventricles are two ___ ventricles and a third and fourth ventricle. ## Footnote (Herlihy, 2020, p. 195)
choroid plexus lateral ## Footnote (Herlihy, 2020, p. 195)
273
The ___ ___, a grapelike collection of blood vessels and ependymal cells, is suspended from the roof of each ventricle and within the spinal cord. ## Footnote (Herlihy, 2020, p. 195)
choroid plexus ## Footnote (Herlihy, 2020, p. 195)
274
Water and dissolved substances are transported from the blood across the walls of the choroid plexus into the ___. ## Footnote (Herlihy, 2020, p. 195)
ventricles ## Footnote (Herlihy, 2020, p. 195)
275
As cerebrospinal fluid (CSF) leaves the ventricles, it follows two paths. Some of the cerebrospinal fluid (CSF) flows through a hole in the center of the spinal cord called the ___ ___. The ___ ___ eventually drains into the subarachnoid space at the base of the spinal cord. The rest of the cerebrospinal fluid (CSF) flows from the fourth ventricle laterally through tiny holes, or ___, into the subarachnoid space that encircles the brain. ## Footnote (Herlihy, 2020, p. 195)
central canal central canal foramina ## Footnote (Herlihy, 2020, p. 195)
276
Eventually the cerebrospinal fluid (CSF) leaves the subarachnoid space. Cerebrospinal fluid (CSF) flows into the ___ ___; water and waste diffuse from cerebrospinal fluid (CSF) in the ___ ___ into the blood of the dural sinuses. Blood then flows from the dural sinuses into the ___ ___ and back to the heart. ## Footnote (Herlihy, 2020, p. 195)
arachnoid villi x 2 cerebral veins ## Footnote (Herlihy, 2020, p. 195)
277
Cerebrospinal fluid (CSF) is formed across the walls of the choroid plexus within the ventricles, circulates throughout the ___ space around the brain and spinal cord, and then drains across the ___ ___ into the dural sinuses. ## Footnote (Herlihy, 2020, p. 195)
subarachnoid arachnoid villi ## Footnote (Herlihy, 2020, p. 195)
278
The rate at which cerebrospinal fluid (CSF) is formed must equal the rate at which it is drained. If excess cerebrospinal fluid (CSF) is formed or drainage is impaired, cerebrospinal fluid (CSF) will accumulate in the ___ of the brain, increasing the pressure within the skull. If the flow of cerebrospinal fluid (CSF) occurs before the sutures in the skull fuse, the child may develop ___, increased intracranial pressure, increased cranial diameter, and brain damage. Fortunately, shunting procedures restore the flow of cerebrospinal fluid (CSF) by surgically creating a detour around the blocked pathway. ## Footnote (Herlihy, 2020, pp. 195, 196)
ventricles hydrocephalus ## Footnote (Herlihy, 2020, pp. 195, 196)
279
Cerebrospinal Fluid ## Footnote (Herlihy, 2020, p. 197)
## Footnote (Herlihy, 2020, p. 197)
280
The ___-___ barrier is an arrangement of cells, particularly the glial astrocytes and the selectively permeable capillary cells; they act as a barrier to the movement of potentially harmful chemicals into the central nervous system (CNS). ## Footnote (Herlihy, 2020, p. 196)
blood–brain ## Footnote (Herlihy, 2020, p. 196)
281
The ___ and the ___ cells select the substances allowed to enter the central nervous system (CNS) from the blood. For example, oxygen, glucose, and certain ions readily cross the membrane. However, if a potentially harmful substance is present in the blood, the cells of the blood-brain barrier prevent that substance from entering the brain and the spinal cord. ## Footnote (Herlihy, 2020, p. 196)
astrocytes capillary ## Footnote (Herlihy, 2020, p. 196)
282
Although the blood–brain barrier is successful in screening many harmful substances, not all toxic substances are blocked. ___, for example, crosses the blood–brain barrier and affects brain tissue. ## Footnote (Herlihy, 2020, p. 196)
Alcohol ## Footnote (Herlihy, 2020, p. 196)
283
If a person has an infection within the central nercous system (CNS), the blood–brain barrier may present a problem in the pharmacologic treatment of the infection. Most ___, for example, cannot cross the blood–brain barrier and therefore cannot reach the site of infection. Given this problem, an infection of the central nervous system (CNS) is treated by two options. The two options are to select an ___ that does cross the blood–brain barrier or inject the ___ directly into the subarachnoid space; this mode of drug delivery is called an ___ ___. ## Footnote (Herlihy, 2020, pp. 196, 197)
antibiotics antibiotic x 2, intrathecal injection ## Footnote (Herlihy, 2020, pp. 196, 197)