2.3 : 뇌의 전달자로서의 뉴런

Neurons, the excitable cells of the nervous system, specialize in transmitting information through electrical and chemical signals in the body.

A neuron is comprised of three fundamental parts– the cell body, the dendrites, and the axon.

The cell body, or soma, contains the cytoplasm and the nucleus, which generate substances needed for the growth and maintenance of the neuron.

Dendrites, extending from the cell body like branches of a tree, receive information from other neurons. Their increased surface area facilitates connections with numerous neurons.

The axon transmits information away from the cell body to other neurons or muscles. For instance, it can stretch over three feet, associating the brain with the spinal cord and featuring several branches to communicate with multiple cells.

A thin, semipermeable membrane envelops neuronal cytoplasm and features channels that allow selective passage of substances.

Most axons are wrapped in a myelin sheath, a layer of fat-containing cells that insulates and speeds up nerve impulse transmission by preventing signal loss and enabling faster impulse travel along the axon.