Cellular Organization of the Nervous System Flashcards
what are the cells of the CNS
neurons, glia, and blood vessels
what are the different types of glia cells
astrocytes, oligodendrocytes, microglia, and ependymal
list the different organelles of a neuron
Golgi bodies, nucleus, mitochondria, lysosomes, and endoplasmic reticulum
what 3 organelles are restricted to the soma of a cell
nucleus, gogli apparatus, and rough endoplasmic reticulum
what are the four main components of a neuron
soma, dendrites, axon, and presynaptic terminals
soma
synthesizes a large quantity and variety of proteins used as neurotransmitters (grey matter)
dendrites
serve as main input sites for the cell (white matter)
axon
output unit of the cell, specialized to send information to other neurons, muscle cells, or glands
presynaptic terminal
transmit elements of the neuron
where are pyramidal cells
cerebral cortex
where are neuroendocrine cells
hypothalamus
where are spiny neurons located
corpus striatum
where are basket cells located
cerebellum
multipolar axon and function
multiple dendrites coming off around cell body
-specialized to receive and accommodate huge amounts of synaptic input to their dendrites
bipolar axon and location/function
one dendrite feeding into the cell body
-found in retina and olfactory receptors
pseudounipolar axon and location/function
single projection from cell body that divides into two axonal roots
-allows faster conduction of action potentials
-conducts sensory info from periphery
where are spinal sensory ganglia found
in intervertebral foramina
where are cranial sensory ganglia found
located in or outside of cranial bones through which the sensory nerves pass through the
axoplasmic transport
transport of membranous and skeletal substances along an axon
anterograde
fresh components are synthesized in the soma and sent toward the presynaptic terminal
retrograde
worn-out materials from the synapse back to the soma for degradation in the lysomes
leak channel
allow diffusion of small number of ions through the membrane at a slow continuous rate
modality gated channels
open in response to mechanical forces, temperature changes, or chemicals
ligand gated channels
open in response to a neurotransmitter, generate local potentials
voltage gated channels
open in response to change in electrical potential across membrane
saltatory conduction
quick node-to-node jumping of action potential down myelinated axon
convergence
multiple inputs from a variety of cells terminate on a single neuron
divergence
single neuron with many branches that terminate on a multitude of cells
microglia cells
act as CNS immune system, clean up and remove debris
3 types of macroglia cells
astrocytes, oligodendrocytes, and Schwann cells
astrocytes
homeostasis, maintaining blood-brain barrier, modulation
oligodendrocytes
forms myelin in CNS
Schwann cells
forms myelin in PNS
ependymal cells
line ventricular system in brain and central canal
-CSF homeostasis, brain metabolism, and clearance of waste from brain
