Nervous Tissue 1: Flashcards
What are the 3 anatomic parts of nervous system and what do they contain?
Central Nervous System:
Brain and Spinal Cord
Peripheral Nervous System:
Cranial Nerves, Spinal Nerves
Afferent sensitives and Efferent Motors
Autonomic Nervous System:
Sympathetic
Parasympathetic
What are the two types of neurons in the CNS that regenerate along the life:
Olfactory
Hippocampus
What is a pericaryon?
The neuron cell body
What are some properties that are specific to neurons?
A very well developed endoplasmic reticulum (ER):
So well developed we can see it
ER can disappear if the neurons connections are taken away
Golgi also very developed
Neuron rich in mitochondria
What are corps de Nissl?
Parts of the cytoplasm that we can see due to a well developped ER
What is lipofuscin?
action des lysosomes qui s’accumulent avec l’âge
What is one cytoplasmic component that we do not find in axons?
What does this mean for the axon?
Ribosomes
As such all of the products are created in the neuron body and sent to the axon
What are microtubules?
Proteins that allow transportation of molecules in the neuron
The transportation is bidirectional:
Retrograde → from axon to body
Anterograde → from body to axon
Difference between slow and fast anterograde flux?
Flux anterograde lent: Important in healing of the axon
Flux anterograde rapide: important for vesicles, mitochondria and other proteins
What are the main protein transporters for retro and antero transportation?
Kinesin for anterograde
Dynein for retrograde
What are some properties of Dendrites?
No myelin
Dendrites contain endoplasmic reticulum
Each “epine dendritique” will get information from one single axon
What kind of flow do we find in electrical synapses?
bi-directional
What are the three neuron morphologies and where do we find each?
When we say multi we are talking about the dendrites
Multipolar
Motor neurons (pyramidal)
Pyramidal neurons have many dendritic projections
Bipolar
Sensoriel neurons (olfaction. hearing, taste)
Pseudo-unipolar
Continued dendrite to axon
Sensitive neurons
Role of astrocytes:
Their main role is support however they also play an important role in neuron activity
- Control the environment of the neurons
- Can bring nearby blood vessels towards the neuron
They also contribute in the creation of the brain blood barrier:
Barriere hemato-encephalique
This barrier can also block medicine to pass the the brain
The astrocites will only be in contact with non myelinated portions of the neuron
- Dendrites
- Synapses
Synaptic transmission role:
- Astrocyte can pick up any excess molecules to prevent hyper-excitation
Role of ependyme
Cells that line all of the ventricles of the brain
Produce the liquide cephalo-rachidien: Plexus choroide
Reabsorb it
Important in orienting the liquide cephalorachidien
What are satellite cells?
Satellite cells are glial cells found in the peripheral nervous system (PNS). They provide support to neurons, regulate the microenvironment, maintain ion balance, and assist in nutrient exchange. They also modulate neuron activity and respond to injury or inflammation in the PNS.
Is the chemical composition of schwan and oligodendricytes the same?
No, that is why some diseases will target one and some the other
If you have an axon covered by schwan cells but not myelinated what is this?
The schwan cell is covering a bunch of non-myelinated axons (like pain fibers) to protect them
- Quel est le rôle du flux axoplasmique dans les neurones?
- A) Formation de la gaine de myéline
- B) Synthèse des protéines
- C) Transport des molécules à travers l’axone
- D) Transmission synaptique
- C) Transport des molécules à travers l’axone
- What is the function of the endoplasmic reticulum (ER) in neurons?
- A) Protein synthesis
- B) Synaptic transmission
- C) Myelination
- D) Neuron multiplication
- A) Protein synthesis
- Which division of the autonomic nervous system is responsible for the release of adrenaline and noradrenaline?
- A) Parasympathetic
- B) Sympathetic
Sympathetic
- Which cells line the ventricles of the brain and produce cerebrospinal fluid?
- A) Astrocytes
- B) Oligodendrocytes
- C) Ependymal cells
- D) Schwann cells
Ependymal cells
