which components of cells are physically connected by a gap junction
Gap junction Gap junctions are a specialized intercellular connection between a multitude of animal cell-types.[1][2][3] They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells.[4][5]
Nervous system The nervous system is defined by the presence of a special type of cellâ€”the neuron (sometimes called "neurone" or "nerve cell").[4] Neurons can be distinguished from other cells in a number of ways, but their most fundamental property is that they communicate with other cells via synapses, which are membrane-to-membrane junctions containing molecular machinery that allows rapid transmission of signals, either electrical or chemical.[4] Many types of neuron possess an axon, a protoplasmic protrusion that can extend to distant parts of the body and make thousands of synaptic contacts;[12] axons typically extend throughout the body in bundles called nerves.