Nervous Tissues Structure of neuron A neuron is

Nervous Tissues

Structure of neuron Ø A neuron is composed of two main parts: ü 1) Cell body. ü 2) Axon. Ø The cell body is a fusiform, round, or polygonal body that contains a round central nucleus surrounded by the cytoplasm that fills the lumen of the cell body.

Structure of neuron Ø Dendrites extend from the cell body towards outside, they receive signals and send them to the cell body, thus, these dendrites are named the receiving part. Ø The cell axon is a long extension of the cell body terminating in a group of branches called axon terminals that make synapses with the dendrites of another cell.

Structure of neuron Ø The axon is sometimes not covered or covered by a very complex fatty chemical substance called myelin sheath, this coating gives the nerves a white color, and is surrounded externally by a thin membrane called neurilemma. Ø This coating performs electrical insulation function to prevent the leakage of nerve emissions that flow through the axon in the form of weak electrical charges, moreover, it also maintains the axon integrity and vitality.

Structure of neuron Ø Secreting of myelin sheath is performed by Schwann cells. Ø Myelin sheath extends along the axon of the neuron, although in its path there are some constrictions that form the so-called Ranvier nodes relative to its discoverer.

Structure of neuron Ø The axon is the part that transmits or conducts nerve signals from the body of the neuron to the outside, as it carries these signals to the receiving part or dendrites of another cell, and this process takes place at the end of the axon when it joins these dendrites at synapses, or when it joins an organ fed by a nerve, as occurs when nerves join muscles in an area called the motor end plate.

Structure of neuron

End of Lecture