The substances that relay the original message from the receptor site to the firing mechanism of the neuron are:

Question

Quizplus · Accepted Answer

Second messengers are the substances that relay signals received at receptors on the cell surface to target molecules in the cytosol or nucleus. They essentially "relay" the original message from the receptor site to the firing mechanism of the neuron, amplifying the strength of the signal.

The Substances That Relay the Original Message from the Receptor