Chemicals released to carry a signal across a synapse are called

1. A signal travelling down an axon reaches a synapse or a neuro muscular junction. 2. It cannot jump the gap electrically at a chemical synapse. 3. Chemicals called neurotransmitters carry the signal across instead. 4. Hormones also act chemically but travel in blood to distant targets, not across a synapse. 5. That distinction, local versus circulating, is what separates neural from endocrine control. _Source: syllabus Biology Ch18 'Neural Control and Coordination', section 18.3_