Lecture 21 Flashcards
Where is grey and white matter situated?
Grey on edges of brain and central butterfly shape in spinal cord.
White centre of Brian and edges of spinal cord.
Grey matter function
Non myelinated and contains cell bodies
White matter function?
Contains myelinated nerve fibres that form ascending and descending tracts from Brian down spinal cord.
What’s the CNS equivalent of Schwann cells?
Oligodendrocytes
What do integrative neurons do?
Found in th CNS they collate all information
Where are pseudounipolar (unipolar), bipolar and post synaptic autonomic neuron cell bodies found?
Outside the CNS
What are the majority of nerves in the CNS?
Interneurons
Different neuron structures?
Multipolar- one axon multiple dendrites
Unipolar- single process from soma
Anaxonic- dendrimer no axon
Bipolar- one axon one dendrite
Role of microtubules in neurons?
Transport vesicles and mitochondria
What process describes the release of neurotransmitter?
Porocytosis
What are the three connective tissue layers that cover nerves?
Epineurium- separates different nerve types and fills space between fascicles
Perineurium- surround fascicles
Endoneurium- surrounds single nerve cells
Paraneurium- separates nerves from surrounding structures
What is the dorsal and ventral horn?
Dorsal= back lobes of grey matter butterfly
Ventral= front lobes of grey matter butterfly
Where is the Schwann cell in unmyelinated neurons?
In the centre with axons around it
How does myelination occur?
Schwann cell surrounds an axon
The Schwann cell surrounds the axon
It begins to wrap around forming multiple layers
The cytoplasm of the Schwann cell is forced out into the cell body
What is the big difference between Schwann cells and oligodendrocytes other than their location?
Oligodendrocytes wrap around multiple axons simultaneously
