Study Guide: Cells of the Nervous System Flashcards
Action Potential: Initiated at
at the axon hillock (or first node of Ranvier in the case of primary sensory neurons).
- Spinous Neurons: Have dendritic spines; through which they receive
excitatory synapses.
Pyramidal neurons of the cortex are an example of:
spinous neurons
- Aspinous Neurons: Lack spines; often are:
inhibitory interneuron
bipolar neurons are found in:
sensory organs
Anaxonic neurons are found in:
retina and olfactory bulb
Aspinous Neurons: Lack spines; often
inhibitory interneurons (but some inhibitory neurons can be spinous)
bipolar neurons are found in sensory organs : more precisely in:
reteina and olfactory epithelium
Anaxonic neurons communicate via:
graded potentials
pseudounipolar neurons are found in
sensory ganglia
Pseudounipolar neurons are found in sensory ganglia of:
Spinal and cranial nerves
Anaxonic neurons lack a :
distinct axon
Anaxonic neurons communicate via:
Graded potentials
Anaxonic neurons are founf in the :
retina and olfactory bulb
most common type of neuron in vertebrates?
multipolar neuron
4 subtypes of multipolar neurons?
(1) Pyramidal cells
(2) Purkinje cells
(3) Granule Cells
(4) Stellate cells
Pyramidal cells are located in what 3 brain regions:
cortex
hippocampus
amygdala
Pyramidal cells are inhibitory/ excitatory?
Excitatory - Glutamate
Purkinje cells are located where?
cerebellum
purkinje cells are excitatory/ inhibitory?
inhibitory - GABAergic
Granule cells are located in (2):
(1) Granular layer of CEREBELLUM
(2) DENTATE GYRUS of the hippocampus
Stellate Cells are excitatory /inhibitory:
excitatory interneurons
Chandelier cells : inhbitory or excitatory?
inhibitory - gabaergic
CHANDELIER CELLS location in cortex:
layer II, III and V
2,3,5
Interneurons are most numerous in:
CNS
Interneurons can be:
local circuit neurons (short axons) or projections neurons (Long axons)
What is an example of modulatory neurons?
Dopaminergic neurons
Modulatory neurons:
Release NEUROMODULATORS that REGULATE neural activity without directly causing action potentials
Local circuit neurons:
short axons
Projection neurons:
long axons
Cholinergic Neurons: found (2):
basal forebrain, brainstem
*Dopaminergic Neurons found (2):
substantia nigra, ventral tegmental area
Form blood-brain barrier
- Astrocytes
Maintain ion balance (K+ regulation)
- Astrocytes
o Act as immune cells in the brain.
o Mediate inflammation and remove debris.
- Microglia
o Line brain ventricles and spinal cord central canal.
o Regulate cerebrospinal fluid (CSF) flow
- Ependymal Cells
o Oligodendrocytes:
CNS, can myelinate multiple axons.
o Schwann Cells
: PNS, myelinates only one axon
- Multiple Sclerosis (MS):
o Autoimmune disease attacking CNS myelin.
o Slows/stops nerve conduction
- Traumatic Brain Injury (TBI):
o Diffuse axonal injury occurs in severe head trauma.
Chandelier cells primarily target which part of the postsynaptic neuron?
Axon initial segment
Golgi Type 1 neurons are characterized by:
long axons that connect different regions
Golgi Type I neurons are characterized by:
Very long axons that connect different parts of the system
Golgi Type II neurons:
Also known as microneurons, have only short axons or sometimes none
Bipolar neurons are primarily found in which sensory system?
Olfactory and visual systems
Pseudounipolar neurons are commonly found in:
Sensory ganglia of cranial and spinal nerves
Where are Purkinje neurons primarily found?
cerebellum
whichh neurotransmitter is primarily used by puyramidal neurons?
Glutamate
in which cortical layers are pyramidal neurons most commonly found?
Layers III and V
STELLATE CELLS are primarily found in which cortical layer?
Layer 4 - IV
