21. Nervous Tissue Structure And Function Flashcards
What are the 2 parts of the nervous system?
CNS - brain and spinal cord
PNS - cranial nerves and spinal nerves
What neurons are present in the CNS and PNS?
CNS - relay
PNS - sensory, motor
What is grey matter?
Peripheral in brain and in areas called nuclei
Central in spinal cord (butterfly shaped)
Has nerve cell bodies, dendrites, axon terminals, non-myelinated axons, neuroglia
What is white matter?
Central in brain
Peripheral in spinal cord
Has myelinated material
Has nerve fibres that form ascending and descending tracts
What are the anterior and posterior prongs in the great matter referred to?
Ventral and dorsal horns, connected by grey commissure
What is the outer connective tissue layer surrounding the spinal cord called?
Pia mater
What are the properties of a neuron?
Many dendrites
Single axon
Often myelinated
Which parts of a neuron are in the CNS?
Main cell body
Dendrites
Proximal part of axon
Which parts of a neuron are in the PNS?
Distal axon
Arborisations
What is the myelin for the axon produced by and is part of in the CNS and PNS?
CNS - oligodendrocyte
PNS - Schwann cell
Describe a motor neurone
Located in CNS to periphery
Function is to end signals to effector tissues
Describe a sensory neurone
Located in periphery towards CNS
Function is to send environmental signals to integrative centre
Have ganglions along axon, both pseudounipolar and bipolar
Describe integrative neurons
Located in the CNS
Function is to collate all information
Can be pyramidal, interneurons or purkinje cells
Describe anaxonic neurons
Location is in retina
Function is to act as relays and thought to hold memory
No axons but many dendrites
Which cell bodies are located outside the CNS?
Pseudounipolar (unipolar)
Bipolar
Postsynaptic autonomic neuron cell bodies
Which is the most predominant cell type in the CNS?
Interneurons