Sheet 1 Flashcards
1
Q
What are the basic functions of the nervous system?
A
1) Sensation (input)
2) Integration (CPU)
3) Reaction (Motor output)
2
Q
What is the sensation function of the nervous system?
A
Receptors monitor changes/events occurring inside and outside of the body (stimuli).
3
Q
Stimuli is mainly what type of energy?
A
Physical energy
4
Q
What are two examples of changes in the internal environment?
A
1) Blood pressure
2) Concentration of certain gases in the blood
5
Q
What are two examples of changes in the external environment?
A
1) Vision (light)
2) Hearing
6
Q
What is the integration (CPU) function of the nervous system?
A
The parallel processing and interpretation of sensory information to determine the appropriate response.
7
Q
Where does integration happened?
A
In the CNS
8
Q
What is the reaction (motor output) function of the nervous system?
A
When the signal moves from the CNS to the periphery, activating muscles to contract and activating glands to secrete (through neurotransmitters).
9
Q
What are the four basic types of tissues in our body?
A
1) Connective tissue
2) Epithelial tissue
3) Muscle tissue
4) Nervous tissue
10
Q
Nervous tissue is _____ (acellular/highly cellular).
A
Highly cellular.
11
Q
What are the two cell types in nervous tissues?
A
1) Neurons
2) Neuroglia
12
Q
What are neurons?
A
The functional unit in the CNS.
13
Q
What are neurons responsible for?
A
Signal transduction
14
Q
Neurons are ______(short-lived/long-lived) and _____(don’t/do) undergo mitosis (cell division).
A
Long-lived; don’t
15
Q
Neurons have:
a) Low metabolic activity
b) High metabolic activity
c) No metabolic activity
d) Depends on the situation
A
B) High metabolic activity
16
Q
Neurons are ______(not electrically excitable/electrically excitable).
A
Electrically excitable.
17
Q
What does electrically excitable mean?
A
Action potential occurs
18
Q
Neurodegenerative diseases occur as a result of what?
A
The neurons’ inability to regenerate.
19
Q
What is the function of neuroglia?
A
Support, nourish, and protect neurons.
20
Q
Neuroglia _____ (do/don’t) undergo mitosis (division).
A
Do.
21
Q
Which type of cell in the nervous tissue is small but outnumbers the other cell by 5 to 50 times?
A
Neuroglia
22
Q
What are the 6 types of neuroglial supporting cells?
A
1) Oligodendrocytes
2) Astrocytes (star-shaped cells)
3) Ependymal cells
4) Microglial cells
5) Schwann cells
6) Stellate cells
23
Q
Which 4 neuroglial supporting cells are found in the CNS (central nervous system?
A
1) Oligodendrocytes
2) Astrocytes (star-shaped cells)
3) Ependymal cells
4) Microglial cells
24
Q
Which 2 neuroglial supporting cells are found in the PNS (peripheral nervous system)?
A
1) Schwann cells
2) Stellate cells
25
What is the function of oligodendrocytes?
Formation of myelin in the myelin sheath, which increases the velocity of action potentials in neurons.
26
What is the function of astrocytes (star-shaped cells)?
1) Aid in the formation of the Blood Brain Barrier (BBB).
| 2) Act as a buffer (get rid of excess neurotransmitters).
27
What is the function of ependymal cells?
They line the ventricles and the central canal of the spinal cord.
28
What are the ventricles?
Hollow spaces in the brain where the cerebrospinal fluid (CSF) passes through.
29
How many ventricles do we have in the brain? Where are they located?
4; 1st and 2nd lateral, 3rd in the midline, and 4th behind the brain.
30
What is the function of microglial cells?
They have phagocytic activity (they are originally monocytes).
31
What is the function of schwann cells?
Form myelin in the PNS
32
What is the function of stellate cells?
Support neurons outside the CNS
33
What are the 3 functional classifications of neurons?
1) Sensory neurons: Carry signals from peripheral (dorsal/posterior root) to CNS.
2) Interneuron (association neuron): Within the CNS.
3) Motor neuron: Its cell body is found within the spinal cord itself. Carries signals from CNS to peripheral through the ventral/anterior root.
34
Which nerve is a mixed neuron (sensory and motor)?
Median nerve
35
What is white matter?
Aggregations of myelinated and unmyelinated axons of many neurons.
36
Does white matter contains neuronal cell bodies?
No it does not.
37
What does gray matter contain?
1) MAINLY neuronal cell bodies
2) Dendrites
3) Unmyelinated axons
4) Axon terminals
5) Neuroglia
38
What causes the difference in color between gray and white matter?
The whiteness comes from the myelin in the white matter; gray matter contains relatively few myelinated axons.
39
What are the parts of a neuron
1) Cell body
2) Axons
3) Dendrites
40
What are nerves?
Bundles of processes (axons and/or dendrites) in the PNS.
41
Give an example of a nerve which contains only axons.
Median nerve
42
Nerves are usually surrounded by what type of tissue?
Connective tissue
43
What are tracts?
Bundles of processes in the CNS. (No connective tissue)
44
What are the two types of tracts?
1) Ascending (Sensory) tracts: From body -> spinal cord -> brain
2) Descending (motor) tracts: From brain -> spinal cord -> body
45
What is a ganglion?
Cluster of nerve cell bodies in PNS.
46
Give 4 examples of ganglions.
1) Dorsal root ganglia
2) Spinal ganglia
3) Trigeminal ganglia
4) Sympathetic chain
47
Ganglion cells are supported by:
Satellite cells
48
What is a nucleus?
Cluster of nerve cell bodies in CNS surrounded by white matter
49
What is a cluster of nerve cell bodies in the CNS not surrounded by white matter?
Cortex
50
 The gray matter is found on the ____(inside/outside) of the brain, while the white matter is found on the ____ (inside/outside) of the brain.
Outside (called the cortex); inside
51
The gray matter is found on the ____(inside/outside) of the spinal cord, while the white matter is found on the ____ (inside/outside) of the spinal cord.
Inside; outside
52
Within each nerve, each axon is surrounded by ____.
An endoneurium
53
Groups of fibers are bound together into bundles (fascicles) by ___.
A perineurium
54
All the fascicles of a nerve are enclosed by ___.
An epineurium
55
What does the central nervous system (CNS) consist of?
1) Brain
| 2) Spinal cord
56
Where is the brain found?
Inside the cranial cavity
57
Where is the spinal cord found?
Inside the vertebral canal
58
The central nervous system is the center of ___.
Integration and control.
59
What does the peripheral nervous system (PNS) consist of?
1) 31 Spinal nerves (carry information to and from the spinal cord and plexuses)
2) 12 Cranial nerves (carry information to and from the brain)
60
How are the spinal nerves spread out?
```
8 Cervical
12 Thoracic
5 Lumbar
5 Sacral
1 Coccygeal
```
61
Name the cranial nerves.
1) Olfactory
2) Optic
3) Oculomotor
4) Trochlear
5) Trigeminal
6) Abducent
7) Facial
8) Vestibulocochlear
9) Glossopharyngeal
10) Vagus
11) Accessory
12) Hypoglossal
62
What are the brain divisions at the embryonic level?
1) Forebrain (Prosencephalon)
2) Midbrain (Mesencephalon)
3) Hindbrain (Rhombencephalon)
63
What is the forebrain (prosencephalon) divided into?
1) Cerebrum (telecephalon)
| 2) Diencephalon
64
What does the Cerebrum (telecephalon) include?
The outer part (Cortex and subcortical white matter)
65
What does the diencephalon include?
1) Thalamus
2) Hypothalamus
3) Epithalamus
4) Subthalamus
66
What does the hindbrain (Rhombencephalon) include?
1) Pons
2) Medulla oblongata
3) Cerebellum
67
Where is the fourth ventricle of the brain located?
Between the cerebellum and the brain stem (it is the cavity of the hindbrain).
68
The brain can also be divided into:
1) Cerebrum
2) Cerebellum
3) Brainstem
(Midbrain, pons, and medulla oblongata)
69
What is the peripheral nervous system responsible for?
Communication between the CNS and the rest of the body.
70
The peripheral nervous system can be divided into:
1) Sensory division (afferent)
| 2) Motor division (efferent)
71
What does the sensory division (afferent) of the peripheral nervous system do?
Conducts impulses from receptors to the CNS and informs the CNS of the state that the body is in, both interiorly and exteriorly. {from special senses (all except taste)}
72
The sensory nerve fibers of the peripheral nervous system can be:
1) Somatic (from skin, skeletal muscles, or joints): felt at a conscious level
2) Visceral (from within organs or body cavities)
73
What does the motor division (efferent) of the peripheral nervous system do?
Conducts impulses from CNS to effectors (muscles to contract or glands to secrete): voluntary
74
What kind of fibers does the motor division (efferent) of the peripheral nervous system have?
Motor nerve fibers.
75
What is the difference between sensory neurons in the somatic nervous system vs the autonomic nervous system?
Somatic: Conducts impulses from receptors to the CNS and informs the CNS of the state that the body is in, both interiorly and exteriorly. {from special senses (all except taste)}
Autonomic: Conducts information to the CNS from autonomic sensory receptors located primarily in the visceral organs (smooth muscle organs in the thorax, abdomen, and pelvis).
76
What is the difference between motor neurons in the somatic nervous system vs the autonomic nervous system?
Somatic: Conducts impulses from CNS to voluntary skeletal muscles.
Autonomic: Conducts impulses from the CNS to involuntary smooth muscles, cardiac muscles, and glands.
77
Give an example for which function sensory autonomic neurons are responsible for.
Detection of blood pressure (baroreceptors)
78
Are signals transmitted through a single neuron?
No, we need several neurons to move the signal along.
79
What is the First Order Neuron?
The neuron that transmits the signal from the periphery to the spinal cord (CNS).
80
What is the First Order Neuron path that a sensory stimulus would take?
Receptor -> (Cell body) Dorsal root ganglia -> axon -> synpase in the spinal cord (dorsal horn)
81
What is the Second Order Neuron?
(Cell body) Dorsal horn of spinal cord ->Ascends up through the spinal cord in a tract (white matter) -> brainstem -> Forebrain/diencephalon -> synapse in the thalamus.
82
What is the Second Order Neuron path that a sensory stimulus would take?
Ascends up through the spinal cord in a tract (white matter) -> brainstem -> Forebrain/diencephalon -> synapse in the thalamus.
83
What is the Third Order Neuron?
The neuron that the Second Order Neuron synapses with.
84
What is the Third Order Neuron path that a sensory stimulus would take?
Thalamus (cell body) -> cortex
85
Where is the cell body of the First Order Neuron found?
Dorsal root ganglia
86
Where is the cell body of the Second Order Neuron found?
Dorsal horn of the spinal cord
87
Where is the cell body of the Third Order Neuron found?
Thalamus
88
What is decussation?
Axons crossing the midline to the opposite side of the spinal cord or brain stem {sensation goes from the right to the left hemisphere}
89
Why do we need more than one neuron?
For neuromodulation: regulation of pathways.
90
How many roots does each spinal nerve have? Name them.
2:
Dorsal (always sensory)
Ventral (always motor)
91
Which neurons could be somatic or visceral (autonomic)?
Motor neurons
92
If a motor somatic response happens, and the skeletal muscle is not in the head/neck region, then which nerves are activated?
Spinal nerves
93
If a motor somatic response happens, and the skeletal muscle is in the head/neck region, then which nerves are activated?
Cranial nerves
94
What is an Upper Motor Neuron?
The neuron that descends through a tract from the cortex synapses with another neuron.
95
Which neuron does the Upper Motor Neuron synapse with?
Interneuron
96
After the Upper Motor Neuron synapses with the interneuron, which nerve does the interneuron synapse with?
Lower Motor Neuron
97
What does the Lower Motor Neuron do?
Transmits the signal to the periphery (skeletal muscles).
98
An upper motor neuron can synapse directly with _____, without needing _____
A lower motor neuron; interneuron
99
____(lower/upper) motor neurons regulate and control the activity of the ____ (lower/upper) motor neurons.
Upper; lower
100
Where are the upper motor neurons’ cell bodies located?
Cortex
101
Where are the lower motor neurons’ cell bodies located?
Ventral horn
102
Where are the interneurons’ cell bodies located?
Gray matter of the spinal cord
103
Which two nerves do not originate from the brain stem?
1) Olfactory
| 2) Optic
104
What is an example of a cranial nerve that has autonomic (parasympathetic) motor fibers?
Vagus nerve
105
Where does the upper motor neuron synapse if the skeletal muscle is not in the head/neck region?
In the ventral horn of the spinal cord
106
Where does the upper motor neuron synapse if the skeletal muscle is in the head/neck region?
In the brainstem
107
What does cell bodies of the lower motor neurons form in the brain stem?
Nucleus
108
What are the high centers of the brain?
The hypothalamus
109
All the autonomic activities in the body are controlled by ___.
The hypothalamus
110
Stimulation of the lower motor neuron always has an ______(excitatory/inhibitory) affect on the skeletal muscle fibers
Excitatory
111
The axon of the lower motor neuron has _____(indirect/direct) control over skeletal muscle fibers.
112
What are the low compartments of the brain?
1) Spinal cord segments
| 2) Brainstem (cranial nerves)
113
Which two neurons are involved in the autonomic nervous system pathway?
1) Preganglionic
| 2) Postganglionic
114
Which neurons carry signals from the hypothalamus and descend to lower compartments?
Higher neurons
115
Which neurons do the higher neuron synapse with?
Preganglionic neurons
116
Which neurons do the preganglionic neurons synapse with?
Postganglionic neurons in the sympathetic or parasympathetic  ganglion
117
Which neuron innervates the visceral motor effectors?
Postganglionic neuron
118
Where does the first motor visceral synapse take place?
1) Brainstem for parasympathetic ONLY
| 2) Spinal cord (Lateral horn of the gray matter)
119
What are the three horns of the spinalgray matter?
1) Dorsal (posterior) horn
2) Ventral (anterior) horn
3) Lateral horn
120
What does the dorsal (posterior) horn do?
Sensory function; First order neurons synapse with the second order neurons here.
121
What does the ventral (anterior) horn do?
Motor function; upper somatic motor neurons synapse with the lower somatic motor neurons here.
122
What does the lateral horn do?
Found in ANS spinal segments ONLY; higher hypothalamic neurons synapse with the preganglionic neurons here.
123
Which spinal segments have lateral horns (ANS segments)?
Sympathetic: Thoracolumbar (All T segments 1-12 + L1-L2)
Parasympathetic: Craniosacral (S1-S5)
124
What is the cranial part of the parasympathetic nervous system?
The brainstem nuclei
125
What is the difference between the ANS ganglia and the dorsal root ganglia?
ANS ganglia contain synapses between pre&post ganglionic neuron cell bodies, while the dorsal root ganglia do not. (They have sensory neuron unipolar or pseudounipolar cell bodies).
