Nervous Tissue - Histology Flashcards
What is a ‘nerve fibre’?
Part neuronal (axon) and part non neuronal (schwann cell).
What are the different layers lof connective tissue of in a mixed peripheral nerve?
Epineurium: Connective sheath around the entire nerve.
Perineurium: Around the bundles.
Endoneurium: around each nerve fibre.
What are each of these structures?
Where would you find the aggregation of the RER near?
What are the structures which could be in the space in red?
RER near where the dendrites are. This is because the dendrites need lots of proteins for the cell membrane proteins.
Mix of dendrites, axons and non neuronal cells blood vessels.
What is the name of the distal region of a nerve axon?
The motor end plate.
What is a terminal bouton?
The name of each synapse with the muscle cell.
There are many boutons per motor end plate.
Where is the nucleus found in a sensory neuron?
In the PNS in the dorsal root ganglion.
hought of as a unipolar neuron because there is one axon which comes out and bifurcates, one goes to the periphery and one goes to the spinal cord. The information actually bypasses the cell body and goes straight to synapse in the CNS. Not the same metabolic activity as motor neurons.
Ganglion: cluster of cell bodies.
In any nerve there is a blood vessel found…..
in the perineurial space.
If there is a nucleus found in a nerve bundle then….
it cannot be from the motor or sensory neuron because the nucleus is found in the dorsal root ganglion or the spinal cord. It must belong to the Schwann cell. If it was in the connective tissue then it may be the fibroblast (to make the connective tissue).
What support does an unmylenated axon get?
They are surrounded by schwann cells but not layers of its plasma membrane. One schwan cell normally covers many unmylentated axons.
How is myelin bound to the axon?
Around the nodes of ranvier (paranodal region), there are many proteins which hold the myelin to the axon.
What can the schwan cell do to the neuronal cell in times of stress?
Can deliver lactate which the neuron can use as energy.