10 Difference Between Medullated And Non-Medullated Nerve Fibre (With Pictures)

Myelinated Vs Unmyelinated
Myelinated (medullated) Vs (non-medulated) Unmyelinated

Get to understand a clear distinction between myelinated and unmyelinated neurons. The basis of comparison include: Speed of transmission, description, node of ranvier, axon, diameter,  impulse conduction and location.

Description Medullated nerve fibre is a nerve fibre with a medullary sheath. Non-medullated nerve fibre is a nerve fibre without medullary sheath.
Alternative Name Medullated nerve fibre is also referred to as myelinated nerve fibre. Non-medullated nerve fibre is also referred to non-myelinated nerve fibre.
Location Medullated nerve fibre is found in the white matter of the brain and spinal cord. Non-medullated nerve fibre is found in the gray matter of the brain and in autonomous nervous system.
Color Medullated nerve fibre is white in color.   Non-medullated nerve fibre is grey in color.
Diameter The diameter of medullated nerve fibre is relatively more than that of non-medullated nerve fibre. The diameter of non-medullated nerve fibre is relatively less when compared to that of medullated nerve fibre.
Nature of Nerve Impulse Conduction Nerve impulse conduction is salutatory. Nerve impulse conduction is smooth.
Nodes of Ranvier Nodes of Renvier are present in medullated nerve fibre at intervals.   Nodes of Ranvier are absent in non-medulated nerve fibre.
Action Potential The action potential does not propagate over the internodes and jumps from node to node. Action potential propagates all along the axon.
Conduction of Nerve Impulse The conduction of nerve impulse in medullated nerve fibre is much faster than in non-medullated nerve fibres. The conduction of impulse in non-medullated nerve fibres is much slower than in the medullated nerve fibre.
Collateral Nerve Fibres Collateral nerve fibres are present in medullated fibre. Collateral nerve fibres are absent in non-medullated  fibres.  
Common Presence Medullated nerve fibres are very much common in vertebrates.   Non-medullated nerve fibres are common in invertebrates, though some vertebrates have non-myelinated nerve fibre.
Voltage-gated ion Channels Voltage-gated ion channels are concentrated at the nodes.   The voltage-gated ions are spread all over the axon.
Extracellular Fluid Extracellular fluid is in contact with the axon only at the nodes. Extracellular fluid is in contact with the axon along its entire length.

Also Read: Difference Between Axon And Dendrite