Question

What is myelin sheath?

Answer 1

Neuron:

1. Neurons are capable of detecting, receiving, and transmitting a variety of inputs.
2. The three major parts of this microscopic structure are the cell body, dendrites, and axons.
3. The axon is a branching fiber with a long distal end.
4. Each branch ends in a synaptic knob, a bulb-like structure that houses synaptic vesicles that contain neurotransmitter molecules.
5. Nerve impulses are transmitted from the cell body to a synapse or a neuromuscular junction through axons.
6. Myelinated and non-myelinated axons are the two types of axons.

Myelin sheath:

1. The myelin sheath is a lipid and protein covering that surrounds the axon.
2. Myelinated nerve fibers are surrounded by Schwann cells, which form a myelin sheath around the axon.
3. The nodes of Ranvier are the spaces between two neighboring myelin sheaths.
4. Myelin sheath electrically insulates the axon of a neuron and increases the speed of nerve impulse conduction.