Most neurons are made up of the following parts: the nucleus (which contains the genetic instructions), the soma (or cell body), dendrites (branch-like structures which receive information from other neurons), axons (long tubular pathways which send information to other parts of the brain), and an (axonal) presynaptic terminal. The presynaptic terminal connects to other neurons via synapses. Many axons are surrounded by myelin, essentially sheaths which help axons quickly send signals over long distances.