Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy > Topic 19: Nervous System > Flashcards

Topic 19: Nervous System Flashcards

1
Q

what are the 2 divisions of the nervous system?

A

-central nervous system (CNS)
-peripheral nervous system (PNS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the central nervous system?

A

-command center
-brain + spinal cord
-processes + integrates info

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what does the peripheral nervous system consist of?

A

-cranial nerves
-spinal nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

where do the cranial nerves go?

A

-to/from the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

where do the spinal nerves go?

A

-to/from the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the 2 divisions of the PNS?

A

-sensory/afferent division
-motor/efferent division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the sensory/afferent division of the PNS?

A

-arriving/going in to the CNS
-has sensory receptors that detect stimuli
-stimuli = changes in the internal/external environments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the motor/efferent division of the PNS?

A

-exiting/going out of the CNS
-nerves convey impulses away from the CNS
-innervates (supplies nerves to) effectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are effectors?

A

-muscles
-glands (exocrine or endocrine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the 2 cells in the nervous system?

A

-neurons
-neuroglia (glial cells)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are neurons?

A

-cells that conduct impulses
-make up the CNS + PNS
-mostly amitotic (irreplaceable)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the structure of a neuron?

A

-cell body
-cell body processes (dendrites + axon)
-can be very long, but are very small in diameter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

which neurons are able to be replaced?

A

-taste
-olfaction
-memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the characteristics of the cell body of a neuron?

A

-contain typical organelles
-rough ER is called nissl bodies
-clusters of cell bodies in the CNS = nuclei (gray matter)
-clusters of cell bodies in the PNS = ganglia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the purpose of dendrites?

A

-receive incoming messages + relay them to the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the purpose of the axon?

A

-carry impulses away from the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the parts of an axon?

A

-axon hillock
-axon terminal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the axon hillock?

A

-where the axon meets the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the axon terminal?

A

-typically branched with synaptic end bulbs (enlarged tips)
- at the end of the axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what can change between axons?

A

-can be myelinated or unmyelinated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what does it mean for an axon to be myelinated?

A

-wrapped in many layers of cell membrane (myelin sheath)
-has electrical insulation (can conduct electrical impulses)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are gaps in the myelin sheath called?

A

-nodes of ranvier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the cells that make up the myelin sheath in the CNS? PNS?

A

-oligodendrocytes (CNS)
-schwann cells (PNS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

where are there myelinated axon bundles?

A

-CNS = tracts (white matter)
-PNS = nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what are unmyelinated neurons?

A

-no myelin sheath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are neuroglia (glial cells)?

A

-support neuron cells
-can undergo mitosis to be replaced
-prone to cancer/brain tumors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what are the 2 types of neuroglia (glial cells)?

A

-CNS neuroglia
-PNS neuroglia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what are the glial cells of the CNS?

A

-oligodendrocytes
-microglia
-astrocytes
-ependymal (neural epithelia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is the purpose of oligodendrocytes?

A

-produce myelin around the axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is the purpose/function of microglia?

A

-protective
-become phagocytic if infected, dead or damaged neurons are detected
-immune cells cannot enter the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is the purpose of astrocytes?

A

-surround blood capillaries to form part of the blood brain barrier
-control capillary permeability of what is leaving + going to the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is the purpose of ependymal (neural epithelia)?

A

-line brain ventricles + central canal of the spinal cord
-secrete cerebrospinal fluid (CSF) + circulate it (cillia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what are the glial cells of the PNS?

A

-schwann cells
-satellite cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is the purpose of schwann cells?

A

-form myelin around axons in the PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is the purpose of satellite cells?

A

-surround neuron cell bodies in ganglia
-protect + support

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what are the structural types of neurons? what are they based on?

A

-unipolar
-bipolar
-multipolar
-based on the # of cell processses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what are unipolar neurons?

A

-have 1 continuous process that divides into 2 (central and peripheral portions)
-peripheral end has dendrites (interact with sensory receptors for pain, touch, etc)
-central end is the axon
-always sensory neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what are bipolar neurons?

A

-2 processes
-1 axon, 1 process with dendrites
-sensory (retina + nose (olfaction) )

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what are multipolar neurons?

A

-3 or more processes
-1 axon + many dendrites
-all interneurons + motor neurons
-most common

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what are the 3 functional types of neurons?

A

-sensory/afferent neurons
-interneurons
-motor/efferent neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what are sensory/afferent neurons?

A

-mostly unipolar
-go from the sensory receptors to the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what are interneurons?

A

-within the CNS
-between sensory + motor
-99% of neurons
-mostly multipolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what are motor/efferent neurons?

A

-CNS to effectors
-all multipolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

what are the different neuron junctions?

A

-neuronal junction
-neuromuscular junction
-neuroglandular junction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

what are neuronal junctions?

A

-neuron to neuron
-can be chemical (use neurotransmitters)
-can be electrical (use ions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what are neuromuscular junctions?

A

-motor neuron to skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what are neuroglandular junctions?

A

-motor neuron to gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

what are the most common neuronal synapses?

A

-chemical neuronal synapses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what is the structure of a chemical neuronal synapse?

A

-presynaptic neuron
-axon terminal
-synaptic cleft
-postsynaptic neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

what is the presynaptic neuron?

A

-neuron bringing the impulse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what is the purpose of the axon terminal in chemical synapses?

A

-the synaptic end bulbs (presynaptic membrane) has synaptic vesicles
-synaptic vesicles contain a neurotransmitter that will be diffused through the synaptic cleft fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

what is the synaptic cleft?

A

-space between neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

what is the postsynaptic neuron?

A

-receives the impulse
-has a postsynaptic membrane
-cell membrane of dendrites or a cell body with receptor sites for the neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

what are the protective features of the central nervous system?

A

-bone
-meninges
-cerebrospinal fluid (CSF)
-blood brain barrier
-cerebral arterial circle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

what is the bone that protects the CNS?

A

-the skull + vertebral column

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

what are meninges?

A

-CT around the brain + spinal cord
-3 layers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

what are the layers of meninges?

A

-dura mater (outer)
-arachnoid mater (middle)
-pia mater (inner)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

what are the characteristics of the dura mater in the brain?

A

-2 fused layers
-separated in spots to form spaces = venous (dural) sinuses (brain only)
-these sinuses contain blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

what is deep to the dura mater for both the brain + the spinal cord?

A

-subdural space
-filled with ISF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what are the characteristics of the dura mater in the spinal cord?

A

-1 layer
-superficial to the dura mater is the epidural space (spinal cord only)
-space is filled with fat, blood vessels, CT, etc (spinal cord only)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

what are the characteristics of the arachnoid mater in the brain?

A

-avascular
-subarachnoid space
-has arachnoid granulations (brain only)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

what are the characteristics of the arachnoid mater in the spinal cord?

A

-avascular
-subarachnoid space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

what is the subarachnoid space?

A

-contains cerebrospinal fluid (CSF)
-web like strands of CT to secure it to the pia mater below

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

what are arachnoid granulations?

A

-project into the dural sinuses
-cerebrospinal fluid (CSF) enters the granulations to return to the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

what are the characteristics of the pia mater in the brain and spinal cord?

A

-on the surface of the CNS
-vascular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

what is meningitis?

A

-inflammation of meninges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

what is cerebrospinal fluid (CSF)

A

-surrounds the brain + spinal cord
-in the brain ventricles + central canal of spinal cord
-cushions the CNS (brain buoyant=floats)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

what forms and produced cerebrospinal fluid (CSF)?

A

-formed from blood plasma (similar composition)
-produced by choroid plexuses (networks) (blood capillaries) found in each ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

what are the brain ventricles?

A

-spaces inside the brain (filled with CSF)
-2 lateral ventricles (1st + 2nd)
-3rd + 4th ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

where are each of the brain ventricles?

A

-1st + 2nd = cerebrum
-3rd = diencephalon
-4th = surrounded by pons, medulla oblongata, cerebrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

what is the central canal of the spinal cord?

A

-space in the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

what cells make the blood brain barrier?

A

-endothelial cells (of capillaries) with tight junctions
-astrocytes with foot processes wrap around the endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

how does the blood brain barrier let stuff through?

A

-selectively permeable
-allows glucose + fat soluble material
-does not allow toxins, antibiotics, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

what is the cerebral arterial circle?

A

-cerebral arteries form a circle at the base of the forebrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

what structures does the cerebral arterial circle circle?

A

-pituitary gland
-optic chiasma (where optic nerves cross)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

what does the cerebral arterial circle unite?

A

-unites the two major blood supplies to the brain (anterior + posterior)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

what does the cerebral arterial circle provide?

A

-an alternate route for blood if the vessels are blocked

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

what are the 3 divisions of the brain/

A

-forebrain
-midbrain
-hindbrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

what is the cerebrum?

A

-right + left cerebral hemispheres
-everything superior + anterior to the cerebellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

what are the lobes of the cerebrum? how are they named?

A

-frontal
-temporal
-parietal
-occipital
-insula (deep to temporal)
-named after the cranial bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

what are the surface features of the cerebrum?

A

-fissures (deep grooves)
-gyri (ridges)
-sulci (shallow grooves)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

what are the 3 fissures of the cerebrum?

A

-longitudinal fissure
-transverse fissure
-lateral fissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

what do each of the fissures seperate?

A

-long. = right + left cerebral hemispheres
-trans. = cerebellum + cerebrum
-lat. = temporal lobe from the rest of the cerebrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

what are two examples of gyri in the cerebrum?

A

-postcentral gyrus in the parietal lobe
-precentral gyrus in the frontal lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

what separates gyri?

A

-sulci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

what is an example of a sulci in the cerebrum?

A

-central sulcus between frontal + parietal lobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

what are the 3 layers of the cerebrum?

A

-cerebral cortex
-tracts
-basal nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

what is the cerebral cortex layer?

A
  • 2-4mm thick
    -gray matter
    -has functional areas
88
Q

what are the functional areas of the cerebral cortex?

A

-motor areas
-sensory areas
-association areas
-other

89
Q

what are the characteristics of the motor areas in the cerebral cortex?

A

-all in the frontal lobe
-control skeletal muscle movement
-3 regions

90
Q

what are the 3 regions of motor areas in the cerebral cortex?

A

-primary motor area (precentral gyrus)
-premotor area
-broca’s area (motor speech)

91
Q

what are the sensory areas in the cerebral cortex?

A

-general sensory area (pain, touch, temp, pressure)
-vision
-auditory + olfaction
-taste + visceral sensation

92
Q

where is the general sensory area?

A

-postcentral gyrus in the parietal lobe

93
Q

where is the vision sensory area?

A

-occipital lobe

94
Q

where is the auditory + olfaction sensory area?

A

-temporal lobe

95
Q

where is the taste + visceral sensation sensory area? what is an example of a visceral sensation?

A

-insula
-full bladder (feeling of internal organs)

96
Q

what are association areas in the cerebral cortex? where are they?

A

-recognize info from memories
-parietal, occipital, + temporal lobes

97
Q

what are other sensory areas in the cerebral cortex? where are they?

A

-memory = temporal lobes
-conscious intellect (personality, learning, ideas, judgement, etc) = prefrontal cortex

98
Q

what are tracts in the cerebrum?

A

-neural pathways
-white matter

99
Q

what are the types of tracts in the cerebrum?

A

-association tracts
-commissural tracts
-projection tracts

100
Q

where do association tracts run from?

A

-gyrus to gyrus in the same hemisphere

101
Q

where do commissural tracts run from? what is an example?

A

-gyrus to gyrus in opposite hemispheres
-ex: corpus callosum

102
Q

where do projection tracts run from?

A

-vertically
-brain to spinal cord/spinal cord to brain

103
Q

what are basal nuclei? what do they control?

A

-paired masses of gray matter (within white matter)
-control skeletal muscle movement

104
Q

what is contained in the diencephalon region of the brain?

A

-thalamus
-hypothalamus
-all gray matter

105
Q

what is the thalamus?

A

-2 lobes connected by an intermediate mass (bridge through the 3rd ventricle)
-relay station for impulses coming to the cortex from the spinal cord

106
Q

what is the hypothalamus?

A

-major regulator of the internal environment (visceral control, blood pressure or heart rate)
-inferior to thalamus, above the pituitary gland

107
Q

what does the midbrain connect? what does it contain?

A

-connects pons + diencephalon
-contains cerebral aqueduct

108
Q

what are contained in the anterior + posterior portions of the midbrain?

A

-anterior = cerebral peduncles (projection tracts)
-posterior = 4 nuclei (corpora quadrigemina)

109
Q

what are the 4 nuclei of the midbrain posterior portion? what is their purpose?

A

-2 superior colliculi (visual reflexes)
-2 inferior colliculi (hearing)

110
Q

what are the parts within the hindbrain?

A

-pons
-medulla
-cerebellum

111
Q

what is the pons of the hindbrain?

A

-tracts between the brain + spinal cord
-tracys to/from the cerebellum
-pontine respiratory centers
-anterior to the cerebellum

112
Q

what is the medulla of the hindbrain?

A

-2 bulges (called pyramids) = large motor tracts = part of the corticospinal tracts
-3 vital centers
-several non vital centers
-inferior to the pons
-ends at the foramen magnum

113
Q

what occurs just above the spinal cord?

A

-decussation (crossover) of pyramids
-axons switch sides (brain sides control opposite sides of the body)

114
Q

what are the 3 vital centers in the medulla?

A

-cardiac
-vasomotor (blood vessels)
-respiratory

115
Q

what are the non-vital centers in the medulla?

A

-swallowing
-sneezing
-vomiting

116
Q

what forms the brain stem/

A

-midbrain
-pons
-medulla

117
Q

what is the cerebellum?

A

-has folds similar to gyri called folia
-cortex is grey matter
-arbor vitae (deep to cortex) is white matter
-coordinates skeletal muscle contraction (balance + posture)
-posterior to pons + medulla

118
Q

what are the 2 functional systems of the brain?

A

-limbic system
-reticular formation

119
Q

what is the limbic system?

A

-regulates emotions (laughing, crying, etc)
-nuclei in the cerebrum + diencephalon
-contains areas involved in memory (memories=emotional response)

120
Q

what is the reticular formation?

A

-regulates alertness + attention
-sleepy when inhibited
-nuclei in brain stem
-cortex + thalamus + hypothalamus are involved

121
Q

how does the reticular formation regulate alertness + attention?

A

-filters stimuli
-sends new/unusual signals to other brain areas

122
Q

what happens if the reticular formation is damaged/

A

-coma

123
Q

what forms the reticular activating system?

A

-cortex
-thalamus
-hypothalamus

124
Q

what is the conus medullaris?

A

-foramen magnum to L1/L2

125
Q

what are the nerves that continue past the spinal cord called? where do they exit?

A

-cauda equina (horse’s tail)
-exits at the intervertebral foramina

126
Q

what is the filum terminale?

A

-CT extension of the pia mater
-anchors the conus medullaris to the coccyx
-where cerebrospinal fluid (CSF) samples are taken

127
Q

what are the parts of the spinal cord?

A

-anterior median fissure (cross-section)
-posterior median sulcus (cross-section)
-central canal
-grey matter
-white matter

128
Q

what do the median fissure and sulcus separate?

A

-seperate the spinal cord into right + left halves

129
Q

what does the central canal of the spinal cord contain?

A

-cerebrospinal fluid (CSF)

130
Q

what is grey matter?

A

-cell bodies + dendrites of motor neurons + interneurons
-H shaped

131
Q

what is the crossbar of the gray H-shaped matter? what about the horns?

A

-cross bar = gray commissures
-dorsal horn = sensory
-lateral horn = motor
-ventral horn = motor

132
Q

what is white matter?

A

-myelinated axons
-contains ascending (sensory) tracts
-contains descending (motor) tracts
-forms 3 columns

133
Q

what are the 3 columns of white matter in the spinal cord?

A

-dorsal column
-lateral column
-ventral column

134
Q

what are the functions of the spinal cord?

A

-sensory + motor impulses
-produces reflexes
-fast + predictable + automatic responses to changes in environment
-ex: withdrawal reflex (arm away from a hot stove)

135
Q

what cranial nerves are associated with the forebrain?

A
  • I olfactory
  • II optic
136
Q

what cranial nerves are associated with the midbrain?

A
  • III oculomotor
  • IV trochlear
137
Q

what cranial nerves are associated with the pons?

A
  • V trigeminal
  • VI abducens
  • VII facial
  • VIII vestibulocochlear
138
Q

what cranial nerves are associated with the medulla?

A
  • IX glossopharyngeal
  • X vagus
  • XI accessory
  • XII hypoglossal
139
Q

which 2 pairs of nerves are only sensory neurons?

A
  • I olfactory
  • II optic
140
Q

which pair of cranial nerves is mainly sensory neurons?

A
  • VIII vestibulocochlear
141
Q

what are the remaining 9 pairs of cranial nerves composed of?

A

-mixed nerves
-both sensory + motor neurons

142
Q

where are the cell bodies of motor neurons located?

A

-brainstem nuclei

143
Q

where are the cell bodies of sensory neurons located?

A

-ganglia of the PNS

144
Q

what is the motor and sensory function of the trigeminal nerve (V)

A

-motor = chewing
-sensory = conveys sensations (touch, pressure, pain, temp) from face to the CNS

145
Q

how many pairs of spinal nerves are there? are they all one type of neuron or mixed?

A

-31
-all mixed nerves

146
Q

where is the location of all 31 spinal nerve pairs?

A

-8 cervical
-12 thoracic
-5 lumbar
-5 sacral
-1 coccygeal

147
Q

where do the spinal nerves exit?

A

-exit at the intervertebral foramina
-1st exits between the atlas + occipital bone

148
Q

what are the 2 points of attachment to the spinal cord for each spinal nerve?

A

-dorsal root
-ventral root

149
Q

what is in the dorsal root?

A

-cell bodies of sensory neurons in the dorsal root ganglion

150
Q

what is in the ventral root?

A

-cell bodies of autonomic + somatic motor neurons in the ventral or lateral horn

151
Q

what forms a spinal nerve?

A

-the joining of the dorsal + ventral roots

152
Q

what do the spinal nerves divide into?

A

-branches called rami

153
Q

what are the 3 rami called?

A

-dorsal ramus
-ventral ramus
-rami communicantes

154
Q

what does the dorsal ramus do?

A

-innervates (supplies with nerves) the skin + muscles of the back

155
Q

what does the ventral ramus do?

A

-forms throacic nerves (T2-T12)
-also may further branch + join to form nerve plexuses (nerve network)

156
Q

what are the 4 spinal nerve plexuses?

A

-cervical
-brachial
-lumbar
-sacral

157
Q

what spinal nerves form the cervical spinal nerve plexus? what is the important nerve that arises?

A
  • C1 - C5
    -phrenic (innervates the diaphragm)
158
Q

what spinal nerves form the brachial nerve plexus? what are the important nerves that arise?

A
  • C5 - C8, T1
    -axillary, radial, ulnar, median, musculocutaneous
159
Q

what spinal nerves form the lumbar nerve plexus? what is the important nerve that arises?

A
  • L1 - L4
    -femoral
160
Q

what spinal nerves form the sacral nerve plexus? what are the important nerves that arise?

A
  • L4 - S4
    -sciatic, divides into tibial + common fibular nerves
161
Q

what is the rami communicantes?

A

-connect the ventral ramus to the sympathetic trunk
-contains autonomic nerve fibres (neurons)

162
Q

what are the wrappings of a nerve?

A

-epineurium (around whole nerve)
-perineurium (around fascicles)
-endoneurium (around axon + myelin)

163
Q

what is the path in the sensory (afferent) division?

A

-stimulus > receptor > CNS

164
Q

what does the sensory (afferent) division of the PNS consist of?

A

-receptors
-first order neurons

165
Q

what is the purpose of receptors?

A

-to detect changes in the environment

166
Q

how are receptors classified?

A

-location
-type of stimulus received
-structure (general senses only)

167
Q

what are the different location receptors?

A

-exteroceptors
-interoceptors
-proprioceptors

168
Q

what stimulus do exteroceptors detect? where are they? what senses?

A

-stimulus in the external environment
-receptors are at the body surface
-touch + special senses

169
Q

what stimulus do interoceptors detect? where are they?

A

-stimulus in the internal environment
-in viscera (organs), blood vessels, etc

170
Q

what are proprioceptors?

A

-monitor body position (stretch receptors, muscle spindles)
-balance + movement
-located in joints, skeletal muscles, etc

171
Q

what are the receptors classified by their type of stimulus?

A

-mechanoreceptors
-thermoreceptors
-chemoreceptors
-photoreceptors
-nociceptors

172
Q

what do mechanoreceptors detect?

A

-mechanical stimuli
-pressure, touch, hearing

173
Q

what do thermoreceptors detect?

A

-temperature

174
Q

what do chemoreceptors detect?

A

-chemical

175
Q

what do photoreceptors detect?

A

-light

176
Q

what do nociceptors detect?

A

-pain

177
Q

what are the two structures of a receptor?

A

-free nerve endings
-encapsulated nerve endings

178
Q

what are free nerve endings?

A

-terminal dendrites of unipolar sensory neurons
-ex: pain, root hair plexus

179
Q

what are encapsulated nerve endings?

A

-terminal dendrites enclosed in CT
-ex: meissner’s + pacinian corpuscles

180
Q

what does autonomic mean?

A

-involves cardiac muscle, smooth muscle, glands

181
Q

what does somatic mean?

A

-involves skeletal muscle

182
Q

what are first order neurons?

A

-unipolar neuron attached or associated with a receptor (may be encapsulated)
-axon travels in cranial/spinal nerves to the CNS

183
Q

where are the cell bodies of the first order neurons?

A

-sensory ganglia of cranial nerves
-dorsal root ganglia of spinal cord

184
Q

where are the axon terminals of the first order neurons?

A

-brain
-dorsal horn of the spinal cord

185
Q

what is the path in the motor (efferent) division of the PNS?

A

-CNS > effector

186
Q

what are the 2 subdivisions of the motor (efferent) division of the PNS?

A

-somatic
-autonomic

187
Q

what is the somatic division of the motor (efferent) division of the PNS?

A

-skeletal muscle = effector
-consists of lower motor neurons

188
Q

what are lower motor neurons?

A

-neurons that have their cell bodies in the lower parts of the CNS (brainstem + spinal cord)
-axons are in the PNS

189
Q

where are the cell bodies of neurons located in the somatic division of the motor (efferent) division of the PNS?

A

-ventral horn of the spinal cord
-motor nuclei of the brainstem
-ex: facial motor nucleus for the cranial nerve VII

190
Q

what is the autonomic division of the motor (efferent) division of the PNS?

A

-smooth muscle, cardiac muscle, glands = effector
-2 consecutive multipolar neurons from the CNS to the effector

191
Q

what are the 2 neurons of the autonomic division?

A

-preganglionic neuron
-postganglionic neuron

192
Q

what is the preganglionic neuron?

A

-myelinated
-cell body in the brain stem or lateral horn of the spinal cord

193
Q

what is the postganglionic neuron?

A

-unmyelinated
-cell body in the autonomic ganglion (outside the CNS)

194
Q

what are the 2 subdivisions of the autonomic division of the PNS (efferent)?

A

-sympathetic (SNS)
-parasympathetic (PSNS)

195
Q

what is the sympathetic nervous system (SNS)?

A

-triggers fight or flight
-cell body of preganglionic neuron in the lateral horn
-autonomic ganglia = trunk ganglia or collateral ganglia
-long axon of the postganglionic neuron
-exit via the thoracic nerves

196
Q

where is the trunk ganglia?

A

-vertically on either side of the vertebral column

197
Q

what is the parasympathetic nervous system (PSNS)?

A

-rest + digest (opposes SNS)
-cell body of the preganglionic neuron in the brain stem + S2-S4
-autonomic ganglia = terminal ganglia
-short axon of the postganglionic neuron
-mainly exit via vagus nerve

198
Q

where is the terminal ganglia?

A

-at or in the organ/effector wall

198
Q

what are the two nervous system pathways?

A

-ascending (sensory)
-descending (motor)

199
Q

what is an ascending nervous pathway?

A

-conducts impulses from general sense receptors into the brain
-3 consecutive neurons from the receptor to the cortex

200
Q

what are the 3 consecutive neurons in the ascending pathways?

A

-first order neuron
-second order neuron
-third order neuron

201
Q

where does the first order neuron of the ascending pathway lead? what type of neuron?

A

-receptor to the spinal cord
-sensory neuron

202
Q

what type of neuron is the second order neuron in the ascending pathway?

A

-interneuron, multipolar

203
Q

where is the cell body of the second order neuron in the ascending pathway?

A

-dorsal horn of the spinal cord or medulla
-crosses over as they go through the brainstem or spinal cord

204
Q

what type of neuron is the third order neuron in the ascending pathway?

A

-interneuron, multipolar

205
Q

where is the cell body of the third order neuron in the ascending pathway? where does it impulse?

A

-in the thalamus
-impulses to the postcentral gyrus (sensory cortex)

206
Q

what forms the ascending spinal tracts?

A

-axons of the first and second order neurons

207
Q

what are the 3 ascending spinal tracts?

A

-dorsal (posterior) column tract/pathway
-spinothalamic tract/pathway
-spinocerebellar tract/pathway

208
Q

what is the dorsal (posterior) column tract/pathway?

A

-receptors with free nerve endings
sensations can be precisely located (touch)
-ex: meissner’s, etc

209
Q

what is the spinothalamic tract/pathway

A

-temperature + pain receptors
-non-specific
-difficult to localize

210
Q

what is the spinocerebellar tract/pathway?

A

-ascending tracts from the spinal cord to cerebellum
-receptors = proprioceptors (body position)
-no third order neuron, second order goes directly to the cerebellum
-no conscious perception
-no crossing over (decussation)

211
Q

what is a descending nervous pathway?

A

-conduct impulses from the brain to the effector
-2 neuron pathway

212
Q

what are the 2 neurons in the descending pathway?

A

-upper motor neuron
-lower motor neuron

213
Q

what is an upper motor neuron? where are their cell bodies located?

A

-multipolar interneurons
-cell bodies are in the cortex or brainstem nuclei

214
Q

what forms the descending spinal tracts?

A

-axons of the upper motor neurons

215
Q

what are the 2 descending spinal tracts?

A

-corticospinal tracts
-indirect tracts

216
Q

what is the corticospinal tract?

A

-cell bodies are in the cerebral cortex
-tracts mainly cross over (decussate) in the medulla

217
Q

what is the indirect tract?

A

-cell bodies are in the brainstem nuclei
-receive impulses from the motor cortex, basal nuclei, and cerebellum

Anatomy (29 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions