NEURO: GLOSSARY Flashcards
neurons
specialised elongated cells (ectoderm)
interconnected through synapses and form chains and networks
perikaryon
enlarged portion of neutron containing nucleus surrounded by cytoplasm
surface- postsynaptic site (receiving synapses)
ganglion
group of perikarya outside CNS
2 types= sensory and autonomous
nucleus
nerve cell group in CNS
dendrites
cytoplasmic processes of neutrons radiating from perikarya
can be straight or wavy
multipolar cells
*primary sensory neurons have no dendrites at all! (pseudopolar neurons)
axon
protrusion on neuron
originates from perikaryon or from main dendrite or from main dendrites with a conic portion (axon hillock)
- axons terminate in en passant and terminal boutons
terminal boutons
end portion of axon, establishing synapses with one or more neutrons.
boutons have vesicles of different sizes, shape and characters.
en passant boutons
synapses from a thickening along the axon proceeding the terminal bouton
grey matter
*consist of neuronal perikarya,
*dendrites,
*initial and terminal portion of axons
*golgi type II interneurons
glial cells
blood vessels
**grey matter occurs in interconnected areas (e.g.. spinal cord), nuclei e.g. brain stem nuclei, or cortical structures (cerebral or cerebellar cortical)
white matter
nerve fibers
glial cells
blood vessels
appears at funiculi (e.g. spinal cord), tracts (e.g. brain stem) or commissural structures (e.g.
nerve fiber
axon surrounded by sheaths! (myelin sheaths or sheath of schwann cells).
axon= nerve fiber
fibers:
alpha: thick myelinated fibers; motoneurons 60-120 m/sec
beta: type 1a muscle
gamma” intrafusal fibers of the muscle spindle
delta: thin myelinated fibers; preganglionic autonomic neurons
B fibers: thin myelinated fibers
C fibers: unmyelinated fibers (sensory and postgnaglionic autonomous neurons)
