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Muscles and glands are not myelinated. It is the axon of a neuron that is myelinated. The myelin forms a layer called myelin sheath that makes the nervous system function properly.
Myelinated nervous tissue is composed of nerve cells with a fatty substance called myelin sheath covering their axons. This sheath acts as insulation, speeding up the transmission of nerve impulses along the axon. Myelinated tissue is found in the brain, spinal cord, and peripheral nervous system.
Unmyelinated axons have slower conduction velocities compared to myelinated axons. Myelinated axons are able to conduct nerve impulses faster due to the insulation provided by the myelin sheath.
White matter in the nervous system is caused when the axons in the area are myelinated. This means that the axons have a fatty protein covering to provide insulation. The myelin sheath is composed of special cells calls Schwann Cells.
Non-myelinated fibers appear as thin, unmyelinated axons within bundles of nerve fibers. They lack the myelin sheath that surrounds some other nerve fibers, which gives them a more transparent or grayish appearance compared to myelinated fibers. Non-myelinated fibers are typically smaller in diameter and conduct nerve impulses more slowly than myelinated fibers.
a nerve fiber that lacks the fatty myelin insulating sheath. Such fibers form the gray matter of the nervous system, as distinguished from the white matter of myelinated fibers. Also called nonmedullated nerve fiber.
Myelinated nerves conduct impulses faster than unmyelinated nerves. The myelin sheath acts as an insulator that allows for faster transmission of nerve signals by increasing the speed at which the action potential travels down the axon.
Unmyelinated nerve fibers conduct impulses more slowly than myelinated nerve fibers. Myelinated nerve fibers have a fatty substance called myelin sheath that allows for faster transmission of impulses compared to unmyelinated fibers without this sheath.
Yes, a myelinated axon can have a larger diameter than an unmyelinated axon. Myelin sheath covers the axon, and the diameter of the axon itself can vary independently of myelination. The larger diameter of a myelinated axon allows for faster conduction of nerve impulses compared to unmyelinated axons.
Nerves are myelinated to increase the speed of nerve impulse conduction. The myelin sheath acts as insulation, helping the nerve signal to travel faster along the axon. This allows for more efficient communication between different parts of the body.
The conduction speed of a nerve fiber is fastest in large myelinated fibers. This is because myelin acts as an insulator, allowing for faster propagation of the action potential by saltatory conduction in large fibers compared to small unmyelinated fibers.
This is called myelin or myelin sheath. It's made mainly from fat with a few proteins in it, and is produced by oligodendrocyte cells in the CNS and schwann cells in the peripheral nervous system. It speeds up nerve signalling by allowing action potentials (the electric currents that make up nerve impulses) to skip between the gaps in the myelin (nodes of ranvier). In unmyelinated axons, sodium and potassium channels have to create the voltage differences at every single step along the nerve. (Say for example 100 times per nerve). Myelinated neurones only need to create these voltage differences at the nodes of ranvier (where sodium and potassium ion channels are located on myelinated neurones) Say for example there are 10 nodes of ranvier on a myelinated axon. The unmyelinated axon must create this voltage difference 10 times more frequently than the myelinated axon, hence the nerve impulse travels 10 times faster in a myelinated axon. (Based on the random numbers I used. In real life the numbers may be wildly different, but they still work in this way).