Chapter 11: Nervous System Flashcards
1
Q
Action potential
A
Nerve impulse
2
Q
adrenal glands
A
triangular-shaped glands on top of each kidney that play a role in the function of the SNS
3
Q
adrenergic fibers
A
nerve fibers that secrete norepinephrine
4
Q
afferent neuron
A
sensory nerve that carries impulses toward the CNS
5
Q
alpha-adrenergic receptors
A
receptors to norepinephrine that generally produce an excitatory response
6
Q
amygdala
A
portion of the limbic system concerned with emotion
7
Q
arachnoid mater
A
delicate meningeal layer lying between dura mater and pia mater
8
Q
autonomic nervous system
A
subdivision of the nervous system responsible for regulating activities that maintain homeostasis; also called visceral motor system
9
Q
axon
A
fiber extending from a neuron’s cell body that conducts impulses
10
Q
babinski sign
A
an abnormal neurological response in older children and adults that involves dorsiflexion of the great toe along with fanning of the other toes when the sole is firmly stroked.
11
Q
basal nuclei
A
masses of gray matter deep within the cerebrum; play a role in the control of movement; also called basal ganglia
12
Q
beta-adrenergic receptors
A
receptors to norepinephrine that generally produce an inhibitory response
13
Q
blood-brain barrier
A
semi-permable membrane that exists throughout the brain that protects the brain of foreign substances
14
Q
brainstem
A
stem-like portion of the brain that connects the cerebral hemispheres to the spinal cord; consists of the midbrain, pons, and medulla oblongata
15
Q
broca’s area
A
area in brain’s left hemisphere responsible for the muscle movements required for speech
16
Q
central canal
A
minute opening through the spinal cord; carries cerebrospinal fluid
17
Q
central nervous system
A
portion of the nervous system consisting of the brain and spinal cord
18
Q
cerebellum
A
portion of the brain responsible for the coordination of voluntary movement and balance
second larges region of the brain; plays a role in sensory, cognitive, and emotional functions
19
Q
cerebral cortex
A
the surface of the cerebrum consisting of a thin layer of gray matter
20
Q
cerebrospinal fluid
A
clear, colorless fluid that fills the brain’s ventricles and central canal and also bathes the outside of the brain and spinal cord
21
Q
cerebrum
A
largest portion of the brain
22
Q
cholinergic fibers
A
nerve fibers that secrete acetylcholine
23
Q
choroid plexus
A
network of blood vessels lining the floor and wall of the brain’s ventricles; charged with creating cerebrospinal fluid
24
Q
corpus collosum
A
thick bundle of nerves that runs along the brain’s longitudinal fissure and joints the two hemispheres of the brain
25
corticospinal tracts
spinal tracts responsible for fine movements of hands, fingers, feet, and toes on the opposite side of the body; also called the pyramidal tracts
26
cranial nerves
nerves of the peripheral nervous system that arise directly from the brain
27
decussation
the action of spinal cord tracts crossing from one side of the body to the other in the brainstem
28
dendrites
portion of neuron charged with receiving signals from other neurons and conducting the information to the body cell
29
depolarization
loss of the difference in charge between the inside and outside of the nerve cell membrane
30
dermatome
a specific area of the skin innervated by a spinal nerve
31
diencephalon
region deep inside the brain that consists of thalamus and hypothalamus
32
dorsal column
relays sensations of deep pressure and vibration in the spinal cord
33
dorsal nerve root
posterior spinal nerve root that carries sensory information into the spinal cord
34
dura mater
tough, outer meningeal layer
35
dural sinuses
spaces created by separations in the dura mater; collect blood that has passed through the brain and is on its way back to the heart.
36
efferent neuron
motor nerve that carries impulses away from the CNS
37
enteric nervous system
network of neurons lining the intestinal tract that communicates with the CNS
38
epidural space
small space between the outer covering of the spinal cord and the vertebrae
39
extrapyramidal tracts
group of spinal tracts associated with balance and muscle tone
40
fascicles
bundles of spinal nerve fibers
41
fissure
deep sulci in the cerebrum
42
frontal lobe
portion of the cerebrum responsible for decision making, reasoning, memory, and voluntary movements
43
glial cells
supportive cells of the nervous system; also called neuroglia
44
gray matter
nervous tissue containing mostly cell bodies of motor neurons and interneurons
45
gut-brain axis
bidirectional communication pathway between the CNS and enteric nervous system
46
gyri
thick ridges in the cerebrum
47
hippocampus
portion of the limbic system charged with converting short-term memory into long-term memory
48
hypothalamus
the bottom half of the diencephalon of the brain, which is responsible for many vital body functions
49
insula
area of cerebrum hidden behind lateral sulcus; plays a role in perception, motor control, self-awareness, and cognitive functioning
50
interneurons
connect incoming sensory pathways with outgoing motor pathways in the CNS
51
limbic system
complex set of structures in the brain responsible for emotion and learning
52
medulla oblongata
attaches brain to spinal cord; contains centers that govern heart rate, blood pressure, and breathing
53
membrane potential
refers to the relative difference of electric charge across the nerve cell membrane
54
meninges
layer of fibrous connective tissue covering the brain and spinal cord
55
midbrain
portion of the brainstem containing tracts that relay sensory and motor impulses
56
mixed nerve
nerve that contains both sensory and motor fibers
57
motor neurons
relay messages from the brain to muscle or gland cells; also known as efferent neurons
58
muscarinic receptors
receptors to acetylcholine on target cells that exhibit a variable response
59
myelin
fatty sheath encasing the axons of many neurons formed by schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system
60
nerve
a bundle of neurons that transmits impulses between the brain and spinal cord and the rest of the body
61
neuilemma
outermost layer of schwann cell; neccessary for nerve regeneration
62
neuroglia
cells in the nervous system that support neurons but do not conduct impulses
63
neurons
nervous system cells that conduct impulses.
64
neuroplasticity
the ability of the brain to physically change
65
nicotinic receptors
receptors to acetylcholine on target cells that produce an excitatory response
66
nodes of ranvier
gaps in the myelin sheath along an axon
67
occipital lobe
portion of the cerebrum responsible for analyzing and interpreting visual information
68
parasympathetic division
division of the autonomic nervous system that primarily has a calming effect; also called craniosacral division
69
parietal lobe
portion of the cerebrum concerned with body sensations and proprioception
70
peripheral nervous system
portion of the nervous system consisting of the network of nerves throughout the body
71
pia mater
innermost meningeal layer covering brain and spinal cord
72
plexus
a network of nerves
73
polarization
the electrical state of a cell membrane that has an excess of positive ions on one side of the membrane and an excess of negative ions on the other
74
pons
portion of the brainstem containing tracts that convey signals to and from different parts of the brain
75
reflex arc
a neural circuit that bypasses regions of the brain where conscious decisions are made
76
refractory period
period immediately after stimulation during which a nerve or muscle is unresponsive to further stimulation
77
reticular activating system
network of nerve pathways in the brainstem that receives sensory input from eyes and ears to maintain state of wakefulness
78
saltatory conduction
conduction of nerve impulses along myelinated axons from one note of ranvier to the next
79
sensory neurons
detect stimuli; also known as afferent neurons
80
soma
nerve cell body; contains the nucleus
81
somatic reflex
reflex involving contraction of a skeletal muscle after being stimulated by a somatic motor neuron
82
spinal nerve
single nerve resulting from fusion of dorsal and ventral nerve roots; carries both sensory and motor fibers
83
spinocerebellar tract
spinal tract responsible for proprioception
84
spinothalamic tract
spinal tract that relays sensations of temperature, pressure, pain, and touch
85
subarachnoid space
separates arachnoid matter from pia mater around the brain
86
subarachnoid space
space between arachnoid mater and pia mater; filled with cerebrospinal fluid
87
subdural space
separates dura from arachnoid mater around the brain
88
sulci
shallow grooves in the cerebrum
89
sympathetic division
division of the autonomic nervous system responsible for the fight or flight response; also called thoracolumbar division
90
synapse
space between the junction of two neurons in a neural pathway
91
synaptic knob
terminal ending of axon branches; contains vesicles containing a neurotransmitter
92
temporal lobe
portion of the brain responsible for hearing, smell, and visual recognition
93
thalamus
area within the diencephalon that acts as gateway for sensory impulses
94
tracts
bundles of axons in the spinal cord that serve as routes of communication to and from the brain
95
ventral nerve root
anterior spinal nerve that carries motor information out of the spinal cord
96
ventricles
four chambers within the brain
97
visceral reflexes
reflex of the autonomic nervous system affecting organs
98
wernicke's area
area in brain's left hemisphere charged with language comprehension; also involved in speech production
99
white matter
nervous tissue containing bundles of axons that carry impulses from one part of the nervous system to another
100
accommodation
the process by which the curvature of the lens changes so the eye can focus on a near object
101
adaptation
the diminishing of a sensation that occurs after continuous exposure to a stimulus
102
analgesic
drug used to relieve pain
103
anterior cavity
space between the lens and cornea of the eye; further divided into an anterior and posterior chamber
104
aqueous humor
clear, watery fluid that fills the anterior cavity of the eye
105
astigmatism
asymmetrical or uneven curvature of the cornea, causing light to be focused unevenlya
106
auditory canal
tube running from the outer ear to the middle ear
107
auditory ossicles
3 small bones that connect the eardrum to the inner ear
108
auricle
visible part of the ear; also called the pinna
109
bony labyrinth
complicated system of passageways within the temporal bone that contains the inner ear
110
canal of schlemm
vessel that collects aqueous humor from the anterior chamber of the eye and delivers it to surrounding blood vessels
111
chemoreceptors
receptors that react to various chemicals, including odors, tastes, and the concentration of various chemicals in the body
112
choroid
highly vascular layer of tissue in the eye that supplies oxygen and nutrients to the sclera and retina
113
ciliary body
thickened extension of the choroid that secretes aqueous humor
114
cochlea
snail-like structure in inner ear that contains the structures for hearing
115
cones
photoreceptors in the retina responsible for color vision
116
conjunctiva
transparent mucous membrane that lines the eyelids and covers the anterior surface of the eyeball
117
cornea
transparent extension of sclera that sits over the iris and admits light into the eyed
118
depth perception
the ability to judge the distance of objects and the spatial relationship of objects at different distances
119
emmetropia
normal vision
120
endolymph
fluid occupying the inside of the membranous labyrinth
121
equilibrium
state of physical balance
122
eustachian tube
passageway from middle ear to nasopharynx
123
external acoustic meatus
opening of the auditory canal to the outside of the body
124
nasolacrimal duct
the passageway that carries tears into nasal cavity
125
nociceptors
pain receptors that respond to tissue damage from trauma
126
olfaction
sense of smell
127
olfactory bulbs
pair of structures residing underneath the brain's frontal lobe
128
pupillary constrictor
muscle encircling the pupil that works to narrow the pupil
129
pupillary dilator
muscle within the iris that works to widen the pupil
130
receptors
structures specialized at detecting a stimulusre
131
referred pain
pain felt in a part of the body other than its actual source; pain originating in a deep organ that is sensed as if it's originating from the body's surface
132
fast pain fibers
produce sharp, localized pain
133
optic chaism
point in the brain where half the optic nerve fibers cross to the opposite side of the brain
134
optic disc
spot where nerve fibers leave the retina, converging to become the optic nerve
135
optic nerve
nerve exiting from the posterior portion of the eyeball; transmits signals to the brain
136
organ of corti
hearing sense organ
137
oval window
opening that leads from the middle ear to the vestibule of the inner ear
138
palpebral fissure
the opening between the eyelids
139
papillae
protrusions on the tongue on which taste buds are located
140
perilymph
fluid that cushions the space between the bony and membranous labyrinth
141
