The size of synaptic cleft (the gap separating nerve cells) in electrical synapse is?

Correct Answer: B. 2nm

Electrical synapses are gap junctions. When present between neurons, they are very different from chemical synapses where the separateness of the cells is not in question. They allow the direct spread of current from one cell to another, without delay or need for receptor and decoding systems. But the individuality of the coupled cells is partly lost, and hence their utility is diminished for large nervous systems with labeled lines like those of mammals. Electrical synapses are common in invertebrate and nonmammalian nervous systems but infrequent in mammals except between neuroglial cells, where they offer the chief mode of communication.