cell-body

The _dendrites_ are short extensions from the cell-body.

Physiology and Hygiene for Secondary Schools Francis M. Walters

The cell-body is smooth and rounded, and its axons extend from it in opposite directions (Fig. 127).

Physiology and Hygiene for Secondary Schools Francis M. Walters

The _axon_, or nerve fiber, is a long, slender extension from the cell-body, which connects with some organ or tissue.

Physiology and Hygiene for Secondary Schools Francis M. Walters

* — The _cell-body_ serves as a nutritive center from which the other parts derive nourishment.

Physiology and Hygiene for Secondary Schools Francis M. Walters

Thus a disturbance at the distant ends of the dendrites causes a movement toward the cell-body and, reaching the cell-body, the disturbance is passed through it into the axon.

Physiology and Hygiene for Secondary Schools Francis M. Walters

It is now known that the protoplasm in all parts of the neuron proper — cell-body, axis cylinder, and dendrites — has a grayish color, while the coverings of most of the fibers are white.

Physiology and Hygiene for Secondary Schools Francis M. Walters

The _dendrites_ serve two purposes: first, they extend the surface of the cell-body, thereby enabling it to absorb a greater amount of nourishment from the surrounding lymph; second, they act as _receivers of stimuli_ from other neurons.

Physiology and Hygiene for Secondary Schools Francis M. Walters

Proof of this is found in the fact that when any part of the neuron is separated from the cell-body, it dies, while the cell-body and the parts attached to the cell-body may continue to live.

Physiology and Hygiene for Secondary Schools Francis M. Walters

It was at one time described as a distinct nervous element, but later study has shown it to be an outgrowth from the cell-body.

Physiology and Hygiene for Secondary Schools Francis M. Walters

In addition to this the cell-body probably reënforces the nervous impulse.

Physiology and Hygiene for Secondary Schools Francis M. Walters