Synapses are

Synapses are

• A. Tiny gaps between dendrites and axons of different neurons
• B. The process of nerve signals traveling within a neuron
• C. The cell that insulates nerve fibers in the peripheral nervous system
• D. The junction where neurotransmitters are released into the bloodstream

Answer: (A)

Synapses are the tiny gaps between neurons where communication happens. At a chemical synapse, the signal is transmitted when the presynaptic neuron releases neurotransmitters into the synaptic cleft, and these chemical messengers cross the gap to bind receptors on the next neuron, influencing its activity. The defining feature here is this junction between neurons, not the inside of a neuron or the insulating cells along peripheral nerves, nor a release into the bloodstream. The option describing small gaps between dendrites and axons of different neurons captures this junction and explains how the signal transfers from one neuron to another. The other ideas refer to processes or structures that are not involved in synaptic transmission: conduction within a neuron, the myelin-insulating Schwann cells, and neurotransmitter release into blood for endocrine signaling.

Synapses are the tiny gaps between neurons where communication happens. At a chemical synapse, the signal is transmitted when the presynaptic neuron releases neurotransmitters into the synaptic cleft, and these chemical messengers cross the gap to bind receptors on the next neuron, influencing its activity. The defining feature here is this junction between neurons, not the inside of a neuron or the insulating cells along peripheral nerves, nor a release into the bloodstream. The option describing small gaps between dendrites and axons of different neurons captures this junction and explains how the signal transfers from one neuron to another. The other ideas refer to processes or structures that are not involved in synaptic transmission: conduction within a neuron, the myelin-insulating Schwann cells, and neurotransmitter release into blood for endocrine signaling.