At the junction where one neuron transmits an impulse to another, what is this called?

The junction where one neuron transmits an impulse to another is known as a synapse. A synapse is a specialized structure that enables communication between neurons; it is the point where the axon terminal of one neuron meets the dendrite of another. This allows for neurotransmitters to be released from the axon terminal and bind to receptor sites on the receiving neuron's dendrites, propagating the neural signal.

This structure is critical for neurotransmission, as it facilitates the transfer of impulses across the gap (known as the synaptic cleft) between two neurons, allowing for the transmission of signals throughout the nervous system. Understanding the role of synapses is essential in studying how neurons communicate and the overall functions of the nervous system.