What are synapses?

Synapses are characterized as tiny gaps between the dendrites of one neuron and the axon of another neuron. This space is critical in facilitating the communication between neurons, allowing for the transmission of signals in the nervous system. When a signal, or action potential, travels down the axon of a neuron and reaches the synapse, neurotransmitters are released into the synaptic cleft (the gap) and bind to receptors on the dendrites of the receiving neuron. This process is essential for the functioning of the nervous system, as it enables signals to move efficiently from one neuron to another, contributing to overall brain function, reflexes, and body responses.

Understanding the role of synapses helps illuminate how information is processed in the brain and how various neurological conditions can arise from dysfunctions in synaptic transmission. Each of the other choices describes components related to neurons but does not accurately capture the definition or function of a synapse. For instance, structures within the cell body of a neuron pertain to intracellular components, while myelin sheaths serve to insulate axons and protect signal integrity, and certain cells do contribute to neuronal protection, but none serve the communicative role defined by synapses.