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| − | ===<u>Fibre Types</u>===
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| − | * Nerve fibres can be assigned to different fibre types depending on their diameter and conduction velocity.
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| − | ** The larger the fibre diameter, the more rapid the rate of impulse conduction.
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| − | ** Particular targets or receptors are associated with axons of a particular diameter, for example:
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| − | *** Those connected to muscles spindles have a large diameter (20 um) and conduct at 120 m/s
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| − | *** The smallest myelinated fibres are about 1um and conduct at around 6 m/s.
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| − | *** The smallest fibres of all are the unmyelinated fibres.
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| − | **** These are the high-threshold sensory afferents, or C-fibres, and post-ganglionic autonomic fibres.
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| − | **** They have a diameter of between 1 and 0.1 um.
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| − | **** These fibres do not conduct by saltatory conduction and have very slow conduction rates of around 0.5 m/s.
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| | ==Connective Tissue== | | ==Connective Tissue== |