Nervous Tissue, spinal cord and spinal nerve (Chp.13-14) Flashcards
(35 cards)
nervous system:
* Maintains ________ coordination with electrical or chemical
messages containing ________ and PNS
* CNS contains _____ & _______ while PNS is all the system except CNS
* PNS contains sensory and motor divisions, further dividing into ________ and ________ divisions.
internal; CNS; brain; spinal cord; somatic; visceral (內臟）Both sensory and motor have both divisions.
Sensory VS Motor:
* Sensory: sends signal to ______; bring sensation
* Motor: sends signals from CNS to _______ or _________ & bring response
Somatic VS Visceral:
* Somatic （身體的）: connect to ______, ________ & ___________.
* Visceral（內臟的）: connect to _________ & ____________.
CNS; gland; muscles; bone joint; skin; muscle; internal organs; involuntary muscles
Properties of neutrons:
* Basic __________
* Excitability: responsive to ___________
* Conductivity: transduce __________
* Secretion: secret __________ to stimulate
another neuron
functional unit; stimuli; signals; neurotransmitters
Neuron mainly contains cell body, ________, ________ and axons.
neurites; dendrites
- Cell body: aka _______
Neurofibrils: network within _______, maintain
________ of neuron - Neurites: _________ or ________
- Dendrites: ________ signals from other cells
- Axons: Conduction of signals to other cells
- Usually enclosed in _________________
soma; soma; shape; axon; dendrites; receive; myelin sheath
- Multipolar:
- One _______ + >2 ________
- Bipolar:
- Two neurites from soma
- One _______ + one ________
- Unipolar:
- _______ neurite from soma
- Pseudounipolar: neurite branches to ______ neurites
axon; dendrites; axon; dendrite; one; two
Pseudo: 假性
I.2.2 Neuroglia
* A.k.a. Glia
* Protects neurons and aids their function
* Glia = Glue
* __________ neurons together via a framework
* Six types of glia in human
* CNS:
1. _________________
2. ___________ cells
3. ___________
4. ___________
* PNS:
1. __________ cells
2. __________ cells
Sticking; Oligodendrocyte; Ependymal; Microglia; Satellite; Schwann
- Oligodendrocyte:
* ___________ body, >10 processes
* The processes wrap axons in CNS, form the ____________ - Ependymal cells:
* Resemble (像） ________________
* Lining ________________ of brain and ______________ of the spinal cord
* Produce ________________ in spinal cord and
_____________
bullous; myelin sheath; cuboidal epithelium; internal cavities; central canal; cerebral spinal fluid; ventricles (腦的空位）
- Microglia
* ________ cells in CNS
* Phagocytic ____________
* Remove dead tissue and foreign materials
* Found in site with injury and infection - Astrocytes
* Most abundant glia
* Many-branched, ________ shape
* Functions: form _________________
* Form __________ barrier,
* restricting material transfer into ______, ________ neurons
* Other functions: chemical balances, promote neuronal/synapse growth, etc
（提供營養）
immune; macrophage; star-like; supportive framework; blood-brain; CNS; protect
血腦屏障=》選擇性地阻止某些物質進入大腦
- Schwann Cells
* Envelop nerve fibers of _______ neurons, forming myelin sheath
* Each Schwann cell wraps only on one myelin sheath
* Assist in _____________________ in PNS - Satellite cells
* Surrounds soma of neurons at regions called _______
* Ganglion: region at ________, where neuronal soma are located
together
PNS; nerve regeneration; ganglion; PNS
- Myelin sheath:
- Insulating layer around nerve fiber
- Formed by:
- _______________ in CNS (one cell,
__________ segments) - _________________ in PNS (one cell, _______
segment) - Composed of protein and ________
- Speed up nerve signal transduction
oligodendrocytes; several; Schwann cells; one; lipid
*Oligodendrocyte可以myelinate mulitiple axons in one cell，但係Schwann cells剩係可以myelinate一個segment in one cell。
ganglion=> a group of neurons
Synapse:
The meeting point between an neutron and another cells (e.g. neuron, muscule,
glandular cells)
* decide if a signal is passed to another cell
* Consists ___________ and postsynaptic neurons
* Forms of synapses:
* ___________: between axon and dendrites
* ___________: between axon and soma
* ____________: between axon and axon
presynaptic; axodendritic; axosomatic; axoaxonic
Two kinds of synapses:
* Chemical:
* With synaptic cleft
* release neurotransmitters
* Electrical:
* With _________________
* Allows __________ diffuse directly
gap junctions; ions
Chemical synapse:
* Cells separated by synaptic cleft
* ____________________(CAMs) connecting ____________________________________________________________
* Neurotransmitters are stored in synaptic vesicles
Common neurotransmitters:
* _________________ (stimulate muscles)
* __________________ (stimulate organs)
* _______________ (excite neurotransmission)
* _____________________(GABA, inhibit neurotransmission)
Cell adhesion molecules; pre and postsynaptic membranes; Acetylcholine; Norepinephrine; Glutamate; Gamma-aminobutyric acid
Brain tumors:
* Usually due to uncontrolled proliferation of ______ cells, not neuron
Diseases of myelin sheath
-Multiple __________（硬化症）:
* degeneration of myelin sheath
* Deterioration of ______________
* May eventually become bedridden (臥床不起）
glial cells; sclerosis; oligodendrocytes
I.4.1 Spinal cord
* ‘’Information highway’’ connects the brain with lower body
* Four principal functions:
1. _____________: conducts information from/to the brain and
other body parts
2. _______________ : integrate information from multiple
sources
3. ______________: controls simple, repetitive muscle contraction
(by __________________________) (中樞模式發生器）
4. ___________: involuntary, stereotyped responses to stimuli
Conduction; Neural integration; Locomotion; Central pattern generators; reflexes
CPGs 是一種不需要傳感器反饋就能產生節律模式輸出的神經網絡
I.4.2 Spinal cord: surface anatomy
* Cylinder of nervous tissue from brainstem
* Passes down the _____________
* In adult: 45cm long, 1.8 cm thick
* Gives rise to ___________ of spinal nerves
vertebral canal; 31 pairs
I.4.2 Spinal cord: surface anatomy
* Divided into 4 regions: _________, ________, ________ & ________ (由上至下）
-Enlargement areas:
* Cervical enlargement: give rise to nerves for _____________
* Lumbosacral enlargement: gives rise to nerves to ____________ and __________
Cauda equina: (Situated in ____________)
* Similar to horse’s tail
* Innervates ___________________
Cervical; Thoracic; Lumbar; Sacral; upper limbs; pelvic region; lower limbs; lumbar; pelvic and lower limbs
Spinal cord (and brain) are protected by membranes named meninges
1. Three layers of meninges:
* ___________ mater:
* Outermost layer
* _________ collagenous membrane
2. ____________ mater:
* _________ array of collagenous/elastic fibers
* _________________ filled with cerebrospinal fluid (CSF)
3. ____________ mater:
* _________, transparent membrane
* ___________ spinal cord to vertebral column at some regions
Dura; tough; arachnoid; looser; sub-arachnoid space; Pia; delicate; anchoring
I.4.3 Spinal cord: cross-sectional anatomy
* Spinal cord consists gray matter and white matters
* Gray matter:
* ____-shaped
* Consists ___________, __________ horns
* Lateral horns at ________ and __________ regions
* ________________ joins right and left sides
* Central canal (space) in middle
* Spinal nerve branches and connects to the spinal cord via _________ and _________ roots
H; posterior; anterior; thoracic; lumbar; Grey commissure; dorsal; ventral
-White matter:
* Surrounds gray matters
* Consists _________ of axons
* Divided into posterior, lateral and anterior _________
bundles; columns
- White matters in spinal cord form __________________
- Types: Ascending tract:
- __________________ up the cord to the brain
- Descending tract: _________________ down to muscle/effectors
- ____________ may be found in tracts
- E.g. left brain sends motor commands to right side of body
spinal tracts; carry sensory information; carry motor impulses; decussation
Ascending Tracts:
* Carry sensory signals up the spinal cord
-Typically has three neurons:
* First-order neuron: ______________, conduct signal to spinal cord
* Second-order neuron: continues to ______________;
* Third-order neuron: carries signal to ______________
* Spinothalamic tract :
* Carries signals for _________, ___________ & ___________
detect stimuli; thalamus; sensory cortex; pain; temperature; pressure
- Descending Tract:
- Carry motor signals down the spinal cord
- Typically involves two neurons:
- Upper motor neuron: from _________ to lower part of spinal cord
- Lower motor neuron: leads to muscle or organ
- Example on right: ________ tract
cortex; corticospinal
