Flashcards in Nervous Tissue CH 11 Deck (41)
Loading flashcards...
1
Functions of the nervous system
1.Sensory input (PNS)
2. Integration (CNS)
3.Motor output (PNS)
2
Peripheral Nervous System (PNS)
Not including the CNS (brain and spinal cord)
Consists or spinal and cranial nreves
3
PNS functional subunits
Afferent
Efferent
4
Afferent Division
Sensory "carrying towards"
1. Somatic sensory fibers: convey impulses from skin, muscles and joints
2. Visceral sensory fibers: transmit from visceral organs (in ventral body cavity)
5
Efferent Division
Motor "carrying away"
1.Somatic NS: voluntary, controls skeletal muscles
2. Autonomic NS: involuntary, controls heart pumping digestion ect.
6
Neuroglia (or glial cells)
6 cells that make us neurons:
7
Neuroglia of the CNS
Astrocytes
Microglial
Ependymal
Oligodendrocytes
8
Neuroglia of the PNS
Satellite cells
Schwann Cells
9
Astrocytes
Most abundant & versatile
Making exchanges between capillaries and neurons
Mopping up leaked K+
Recycling released neurotransmitters
10
Microglial Cells
Type of macrophage
Phagocytize microorganisms and neural debres
Janitor
11
Ependymal Cells
Line CNS cavities
Cilia helps circulate CSF
12
Oligodendrocytes
Form myelin sheaths around CNS fibers
13
Satellite cells
unknown function may be similar to astrocytes
14
Schwann Cells
Vital for regeneration of peripheral nerve fibers.
Form myelin sheath
Similar to oligodendrocytes
15
Dentrites
Receptive, input region
Each neuron has many dentrites
Motor neurons, off the cell body
Short, tapering, diffusley branching extentions
16
Axons
Each neuron has one axon
spender process
long axon = nerve fiber
Conducting region
17
Axon Hillock
cone shaped initial region of the axon
18
Axon Collaterals
Extend from axon at right angles
19
Axon terminals
Secretory region
knoblike distal ends of axon terminal branches
20
Myelin Sheath
White, fatty fibers (protein-lipiod)
Protects, electronically insulates and increases speed on nerve impulse
Only on axons not dendrites.
21
White matter
Myelinated regions of the CNS, primary fiber tracts.
22
Grey matter
Unmyrlinated fibers and contains mostly nerve cell bodies.
23
Nodes of Ranvier
Gaps in myelin sheath
24
Neuron structural classifications
Multipolar
Bipolar
Unipolar
25
Multipolar neurons
3 or more processes (1 axon the rest dendrites)
Most common
Major type in CNS
26
Bipolar neurons
2 processes
(1 axon 1 dendrite)
retina and olfactory mucosa
27
Unipolar neurons
Single short process
emerges from cell body
divides T-like into proximal and distal branches
Found in PNS ganglia
28
Interneurons
Multipolar
lie between sensory and motor
In CNS
29
Action Potential
Nerve impulse, conduction impulse that travels down the axon.
30