Nervous System Flashcards
(101 cards)
1
Q
The ability to respond to stimuli
A
Excitability
2
Q
Production of electrical signals that that travel to other locations
A
Conductivity
3
Q
Production of neurotransmitters at the end of nerve fibres that jump the gap and stimulate the next cell
A
Secretion
4
Q
Two types of cells
A
Neuron
Neurolgia
5
Q
Conducting cell that transmits impulses and is the structural and functional unit of the nervous system
A
Neuron
6
Q
- Non conductive and provide a support system for neurons
* Special type of connective tissue for nervous system
A
Neuroglia
7
Q
Neuron number in the human brain
A
10^11
8
Q
Glia per neuron
A
10-50
9
Q
Neurons are ………….. cells that are highly specialised to detect detect stimuli, respond quickly and transmit codes information to other cells
A
Amitotic
10
Q
Neuron number in body
A
100x10^9
11
Q
Each neuron is connected to …………. other neurons
A
10,000
12
Q
Astroglia
Oligodendroglia
Microglia
Ependyma
A
Neuroglia of the CNS
13
Q
Schwann cells
Satellite cells
A
Neuroglia of the PNS
14
Q
Sensory (afferent) division
A
- Transmits information from the periphery to the CNS
* Contains receptors
15
Q
Receives sensory information from skin, fascia, joints, skeletal muscles and special senses
A
Somatic sensory
16
Q
Receives sensory information from viscera
A
Visceral sensory
17
Q
Motor (efferent) division
A
- Transmits information from CNS to the rest of the body
* Sends motor information to effectors
18
Q
Voluntary nervous system: innervated skeletal muscle
A
Somatic motor
19
Q
Involuntary nervous system: innervated cardiac, smooth muscle and glands
A
Autonomic motor
20
Q
Consists of aggregations of neuronal cell bodies, dendrites, unmyelinated axons and neuroglial cells
A
Gray matter
21
Q
Gray appearance in grey matter is caused by ……………..
A
Absence of myelin
22
Q
Composed mostly of myelinated nerve fibres along with some unmyelinated fibres and neuroglial cells
A
White matter
23
Q
Axons, dendrites and neuroglial processes form a tangled network of neural tissue called:
A
Neuropil
24
Q
Aggregations of neuronal cell bodies embedded with white matter
A
Nuclei
25
Aggregations of cell bodies in the peripheral nervous system
Ganglia
26
Gray matter location in brain
Periphery(cortex) of the cerebellum and cerebrum and forms the deeper basal ganglia
27
White matter location in brain
Deep to the cortex and surrounds the basal ganglia
28
White matter location in the spinal cord
Periphery of spinal cord
29
Gray matter location in the spinal cord
Deep in the spinal cord where is forms an H shape in cross section
30
Spinal cord functions in nerve coordination
* Coordinating centre for the reflex arc
| * Connecting network between peripheral nervous system and the brain
31
Conduction of nerve impulses towards the nervous system
Afferent
32
Conduction of nerve impulses swag from the nervous system
Efferent
33
Afferent nerve fibres arise:
From the senses
34
Efferent (motor nerves) arise from:
Central nervous system
35
Efferent (motor nerves) include:
* Somatic nerve fibres(innervate skeletal muscles)
| * Autonomic nerve fibres(innervate smooth, cardiac muscles and glands)
36
Reflexes
* Require stimulations
* Are quick
* Stereotyped
* Involuntary
37
The nervous system develops from the ............... of the embryo in response to signalling molecules from the ............
Ectoderm
| Notochord
38
At the beginning of the third week, the .............. has the shape of a .......... that is broader in the ............ than in the caudal region
Ectodermal germ later
Disc
Cephalic
Caudal
39
Notochord releases signalling molecules that induce ectoderm to form ............ which thickens and forms the ............
neuroepithelium
| Neural plate
40
Neural plate forms ........... whose edges continue to grow towards each other forming the ...........
neural groove
| Neural tube
41
Rostral(anterior) end of the neural tube develops into
The brain
42
Caudal(posterior) portion of the neural tube develops into:
Spinal cord
43
Neural tube additionally gives rise to
* Neuroglia
* Ependyma
* Neurons
* Choroid plexus
44
Neuralation
Process of neural tube formation
45
Neuralation stages
* Shaping(neuroepithelum to neural plate)
* Bending (neural plate)
* Fusion (neural folds to neural tube)
46
Cells lining the groove are ............. which give rise to all the cells of the ..........
Neuroepithelial cells
| CNS
47
Ectoderm at the margins of the neural folds represent cells destined to become ............ that will give rise to the main elements of the .........
Neural crest cells
| Peripheral nervous system
48
* Fusion of the neural tube begins in the .............. and proceeds cranially and caudally.
* Until fusion is complete, the cephalic and caudal ends of the neural tube communicate with the amniotic cavity through cranial and caudal ..........
* Cervical region (middle of the embryo)
| * Neuropores
49
Cranial neuropore closes at day ....... whereas the caudal at day.........
25
| 27
50
Neural tube layers
Ventricular zone
Intermediate zone
Marginal zone
51
Gives rise to neuroblasts(nerve cells) and glioblasts(supporting cells)
Ventricular zone
52
Neuroblasts and glioblasts in the intermediate zone form two collections of cells called the ............. and the ................ separated by a groove called the ..............
Alar plate
Basal plate
Sulcus limitans
53
Cells in the alar plate become ............ and form the .................. of the spinal cord
Afferent (sensory) neurons
| Dorsal horn
54
Cells in the basal plate become ................ and form the ............... of the spinal cord
Efferent (motor) neurons
| Central horn
55
Between the basal and alar played is ............... that contains neurons of the autonomic nervous system
Intermediate layer
56
Primary brain vesicles
Prosencephalon- Forebrain
Mesencephalon-Midbrain
Rhombencephalon-Hindbrain
57
Above the mesencephalon is the ............... and beneath it is the ...............
* Prosencephalon (future forebrain)
| * Rhombencephalon (future hindbrain)
58
Rhombencephalon
Hindbrain
59
The optic vesicle which will eventually become the
-..........
-..........
-...........
Forms at the basal plate of the ...........
Optic nerve
Retina
Iris
Prosencephalon
60
Prosencephalon develops into:
Telencephalon
| Diencephalon
61
The mesencephalon develops into the:
mesencephalon
62
The rhombencephalon develops into:
Metencephalon
| Myelencephalon
63
Telencephalon develops into:
Cerebrum: cerebral hemispheres(cortex, white matter, basal nuclei)
64
Diencephalon develops into:
Diencephalon(thalamus, hypothalamus, epithalamus, Retina)
65
Mesencephalon develops into:
Brain stem: midbrain
66
Metenceohalon develops into:
Brain stem: pons
| Cerebellum
67
Myelencephalon develops into:
Brain stem: medulla oblongata
68
Spinal cord is a cylinder of nervous tissue that is continuous with the:
Medulla oblongata
69
Spinal cord begins at ............. and passes through the ............. as far as the inferior margin of the first ...............
Foramen magnum
Vertebral canal
Lumbar vertebra
70
Thickness of spinal cord
1.8 cm
71
Length of spinal cord
45cm
72
Divisions of spinal cord
Cervical
Thoracic
Lumbar
Sacral
73
In the inferior cervical region of the spinal cord, a cervical enlargement gives rise to ...........
Nerves of the upper limbs
74
In the lumbosacral region, a lumbar enlargement gives ..........
Nerves to the pelvic region and lower limbs
75
Inferior to the lumbar enlargement, the spinal cord tapers to a point called:
Medullary cone
76
The ................ and ............... give rise to a bundle to nerve roots that occupy the canal of vertebrae .......... to ............. and this bundle is called the ...............
Lumbar enlargement
Medullary cone
L2 to S5
Cauda equina
77
The cauda equina innervates
The pelvic organs and lower limbs
78
Caudal to the conus medullaris is the:
Terminal filament
79
Enlargement of the space in the Dural sac, caudal to the medullary cone containing the cauda equina
Lumbar cistern
80
Lumbar cistern
Extends from level L2 to level S2
81
Spinal cord is suspended in the dural sac by:
Denticulate ligament on each side
82
Denticulate ligament
Lateral extensions from the lateral surfaces of the pia mater
83
Fibrous membranes that enclose the brain and spinal cord
Meninges
84
Meninges function
Separate soft tissue of CNS from the bones of the vertebrae and skull
85
Meninges types from superficial to deep
Dura mater
Arachnoid mater
Pia mater
86
Histologically neurons contain ......... which is mainly composed of rough endoplasmic reticulum
Nissel substance
87
Because of the RNA content nissel substance is:
Highly basophillic
88
is at the apex of the dorsal horn, and contains the posterior marginal
nucleus. These cells respond to thermal and other noxious stimuli, and receive axosomatic connections from lamina II. The dorsolateral tract of Lissauer separates
this lamina from the surface of the spinal cord
Lamina I
89
(substantia gelatinosa) consists of Golgi type II neurons (a nerve cell with a short axon that ramifies in the gray matter of the CNS), receiving fibers that carry pain and temperature sensations. Their axons contribute to the formation of the Lissauer
zone (dorsolateral fasciculus).
Lamina II
90
are rich in substance P (excitatory
| neurotransmitter of pain impulses), in opioid receptors and the enkephalin.
Lamina I and II
91
contain the largest dorsal horn nucleus, the nucleus proprius, which
also exists at all cord levels. It contributes axons to the lateral spinothalamic tract and
receives virtually all sensory modalities carried by the dorsal root (movement,
position, vibration and two-point discrimination from the dorsal white column).
Laminae III and IV
92
occupies the neck of the posterior horn and establishes synapses
with the corticospinal and rubrospinal tracts. The lateral part is known as the reticular nucleus
Lamina V
93
is present in the spinal cord enlargements and particularly absent
in the T4 through the L2 segments. It receives group I muscle afferents in its medial zone, and descending spinal terminations in its lateral zone.
Lamina VI
94
forms the intermediate zone contains the Clarke’s, intermediolateral & intermediomedial
nuclei, and receives fibers from the
corticospinal & rubrospinal tracts
Lamina VII
95
extends from the
C8/T1 through L2/L3, giving rise to the
dorsal spinocerebellar tract
Clarke’s nucleus
96
```
-occupies the lateral horn between the T1 and
the L2/L3 spinal segments, providing
preganglionic sympathetic axons.
-At the S2 through S4, this nucleus
provides preganglionic
parasympathetic fibers
```
Intermediolateral nucleus
97
extends
the entire length of the spinal cord
and receives visceral afferents
intermediomedial nucleus
98
is a zone of heterogeneous cells in the anterior horn most
prominent in the spinal cord enlargements (T1 through L2/L3). It is associated with autonomic function, and contains commissural neurons which receive
axons of the tectospinal, vestibulospinal, and pontine reticulospinal tracts
Lamina VIII
99
contains clusters of large α & γ motor nerve cells in the anterior horn. The larger cells send out α efferent motoneuron axons to the extrafusal skeletal
muscle fibers, while smaller cells send out γ motoneuron axons to the intrafusal
spindle fibers
Lamina IX
100
receives excitatory input from the
descending pathways and the reflex arcs, and inhibitory input from the
propriospinal neurons
Alpha motor neurons
101
consists of small neurons that
form the gray commissures around the central canal. It receives some afferents
from the dorsal root fibers and contains
neuroglial cells in its ventral part that
send cytoplasmic extensions to the
adjacent pia mater
Lamina X
