Unlike an electrical synapse, the chemical synapses are separated by a space called the synaptic cleft, typically measured between 15 and 25 nm. Transmission of an excitatory signal involves several steps outlined below.
Definition of cap. 1  1a : a head covering especially with a visor and no brimb : a distinctive head covering emblematic of a position or office: such as (1) : a cardinal's biretta (2) : mortarboard.
A hard cap for the autumn and winter. The Ascot Cap, also known as the Cuffley Cap, is a menâs cap similar to the flat cap, but distinguished by its hard and rounded shape. Ascot Caps are usually made from felt or wool and they are worn in the autumn or winter. Straw Ascot Caps also exist for the summer.