Dendrites typically branch profusely, getting thinner with each branching, and extending their farthest branches a few hundred microns from the soma. The soma is usually compact the axon and dendrites are filaments that extrude from it. A typical neuron is divided into three parts: the soma or cell body, dendrites, and axon. In vertebrates, the majority of neurons belong to the central nervous system, but some reside in peripheral ganglia, and many sensory neurons are situated in sensory organs such as the retina and cochlea.Īlthough neurons are very diverse and there are exceptions to nearly every rule, it is convenient to begin with a schematic description of the structure and function of a "typical" neuron. The body's neurons, plus the glial cells that give them structural and metabolic support, together constitute the nervous system. The features that define a neuron are electrical excitability and the presence of synapses, which are complex membrane junctions used to transmit signals to other cells. ![]() 5 Mechanisms for propagating action potentialsĪ neuron is a special type of cell that is found in the bodies of most animals (all members of the group Eumetazoa, to be precise-this excludes only sponges and a few other very simple animals). ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |