SDL-2 Neurotcytology & CSF Flashcards
Neurons are said to be __________, based upon their ability to respond to the environment and activity with morphological changes.
Plastic
The neuronal _______ is the metabolic (trophic) center for the neuron.
Soma (cell body)
(T/F) The size of neuronal somas are uniform throughout all neurons.
False. The size of the soma depends upon the function of the neuron, and to a large extent, the length of its processes, the axon in particular.
What effect does axon length have upon the soma?
The longer the axons a neuron possesses, the larger the diameter of the soma.
In general, the dorsal horn contains ________ neurons.
Sensory
In general, the ventral horn contains ________ neurons.
Motor
The three shapes of neurons are __________, __________, and ___________.
Pseudounipolar; bipolar; multipolar
(Pseudounipolar/Bipolar/Multipolar) neurons have a single process that extends from the soma and then bifurcates.
Pseudounipolar
(Multipolar/Pseudounipolar/Bipolar) neurons have two processes that extend from the soma, one of which is an axon, and the other a dendrite.
Bipolar
(Bipolar/Multipolar/Pseudounipolar) neurons have one axon and two or more dendrites extending from the soma.
Multipolar
The most common type of neuron is a (pseudounipolar/multipolar/bipolar) neuron.
Multipolar
(Bipolar/Multipolar/Pseudounipolar) are restricted to the sensory system and are found almost exclusively within the peripheral nervous system.
Pseudounipolar
(Pseudounipolar/Bipolar/Multipolar) neurons are the most rare shape and are found predominately in the peripheral nervous system.
Bipolar
Rough endoplasmic reticulum that has been organized into parallel cisternae with numerous polyribosomes (polysomes) between them is termed ___________.
Nissl substance or bodies
Nissl bodies and ribosomes are found throughout every part of the neuron except for the __________.
Axon
Transport away from the soma is termed ________.
Anterograde
Transport toward the soma is termed _________.
Retrograde
Microtubules involved in transport are more numerous in (axons/dendrites).
Dendrites
Intermediate filaments used for cytoskeleton structure and found in neurons are known as ____________.
Neurofilaments
A granule found in neurons that consists of material undigested by lysosomes is known as a(n) __________.
Lipofuscin granule
(T/F) Lipofuscin granules are greater in young nervous systems due to underdeveloped lysosomes. These lipofuscin granules dissipate as lysosomes mature.
False. Lipofuscin granules are greater in older nervous systems as material undigested by lysosomes increases with age.
Peripheral dorsal root ganglion (DRG) processes (sometimes referred to as dendrites) involved in pain and temperature are (unmyelinated or lightly myelinated/heavily myelinated).
Unmyelinated or lightly myelinated
Peripheral DRG processes (sometimes referred to as dendrites) involved in touch, vibration, and joint position sense are (unmyelinated or lightly myelinated/heavily myelinated).
Heavily myelinated
Neuronal dendrites are generally highly branched, also referred to as being _________.
Arborized
The region of the soma that the axon originates from is called the __________.
Axon hillock
The axon hillock may be distinguished from other cytoplasmic extensions by ________________.
The absence of Nissl bodies
(Neurofilaments/Microtubules) predominate over (neurofilaments/microtubules) in the cytoplasm of the axon (axoplasm).
Neurofilaments predominate over microtubules.
(Neurofilaments/Microtubules) predominate over (neurofilaments/microtubules) in the cytoplasm of the dendrite.
Microtubules predominate over neurofilaments.
(T/F) Unlike dendrites, an axon may leave the CNS and enter the periphery.
True.
Slow axoplasmic transport occurs at a rate of ___________ per day.
2-4mm/day
Fast axoplasmic transport occurs at a rate of ____________ per day.
200-400mm/day
The types of macroglia are ____________ and ___________.
Astrocytes; oligodendrocytes
Astrocytes that contain an abundance of ___________ are classified as fibrous astrocytes.
Glial fibrillary acidic protein (GFAP)
Astrocytes whose processes do not contain much GFAP are termed ___________.
Protoplasmic astrocytes