Nervous Tissue Flashcards
(17 cards)
Retrograde axonal transport uses ____ and moves cargo toward the ___ end of microtubules. Anterograde axonal transport uses ___ and moves cargo toward the ____ end. Which type is used in fast transport? Slow?
Anterograde: kinesin, toward + end (away from cell center)
Retrograde: dynein, toward - end (toward cell center)
Fast transport: antero and retro
Slow transport: antero
Which cytoskeletal proteins are used in neuronal soma for structural support?
actin microfilaments, neurofilaments (intermediate), microtubules
What is myasthenia gravis?
An autoimmune disease directed against acetylcholine receptor, inhibits transmission of nerve impulse from motor neuron (inhibits excitation of sarcolemma)
What is botulism?
Botulin toxin (clostridium botulinum) blocks release of acetylcholine
Which neuroglial cells are located in the CNS? In the PNS?
CNS: Oligodendrocyte, astrocyte, microglial cells
PNS: Satellite cells, Schwann cells
What is the function of oligodendrocytes?
myelin production, insulation of electrical impulses
What is the function of astrocytes?
Structural support, establish blood-brain barrier, ion
homeostasis, neurotransmitter uptake, growth factors
What is the function of microglial cells?
Phagocytic cells (part of MPS)
What is the function of satellite cells?
Structural support, supply growth factors (similar to CNS astrocytes)
What is the function of Schwann cells?
myelin production, electrical insulation (similar to CNS oligodendrocytes)
Motor/efferent impulses are transmitted from the ___ to the ___, and pass through _____ in vertebrae.
CNS, body, ventral root ganglia
Sensory/afferent impulses are transmitted from the ___ to the ___, and pass through _____ in vertebrae.
body, CNS, dorsal root ganglia
The (very thing) connective tissue surrounding individual axons is called the _____. Surrounding fascicles or bundles of axons: ____. Surrounding nerves (multiple fascicles): ____.
endoneurium, perineurium, epineurium
A Schwann cell wraps its own plasma membrane around a single axon in myelinated or unmyelinated neurons?
Myelinated. (It surrounds multiple axons only once in unmyelinated neurons)
Where is the Schwann cell nucleus relative to the axon(s) in myelinated and unmyelinated PNS nerves?
The nucleus lies within the axons in unmyelinated nerves, and is located at the edge of the myelin sheath in myelinated nerves.
Abnormalities in ______ expression cause peripheral nerve diseases. What causes hereditary motor and sensory neuropathy-Type 1 (HMSN-1)? Charcot-Marie-Tooth syndrome-Type 1
(CMT-1)?
Peripheral Myelin Protein 22 (PMP-22)
HMSN-1: mutation in PMP-22 causing demyelination of peripheral nerves
CMT-1: duplication of PMP-22 results in Schwann cell hyperplasia (puts too much pressure on the axon, impedes conduction)
What is different about a peripheral nerve after it has regenerated following injury?
It has an extra node of Ranvier
