What term refers to chemicals that help communication across nerve synapses?

• A. Neurotransmitter
• B. Hormone
• C. Enzyme
• D. Receptor

Answer: (A)

Neural communication across synapses relies on neurotransmitters, chemical messengers released by a neuron into the synaptic gap. They cross the gap and bind to receptors on the Postsynaptic neuron, producing an electrical change that continues or modulates the signal. This chemical step at the junction is what makes rapid, localized signaling possible from one neuron to the next.

Hormones, by contrast, are signaling molecules released into the bloodstream to affect distant targets, not confined to a single synapse. Enzymes are catalysts that speed up chemical reactions and aren’t the signaling chemicals transmitted across synapses. Receptors are the proteins on the postsynaptic cell that detect signaling molecules, but they are the targets or receivers, not the actual messengers crossing the synapse.