Question

a type of chemical released from the tip pf an axon into the synaptic cleft when a nerve impulse arrives

Answer 1

The type of chemical released from the tip of an axon into the synaptic cleft when a nerve impulse arrives is called a **neurotransmitter**. Neurotransmitters are chemical messengers that transmit signals across the synapse from one neuron to another, or to muscle cells or glands. Common examples of neurotransmitters include dopamine, serotonin, acetylcholine, norepinephrine, and glutamate.