Final answer:
Extracellular chemical messengers bring about cell response by signal transduction through receptor binding, signal amplification, and response activation.
Step-by-step explanation:
Extracellular chemical messengers bring about cell response by signal transduction through a series of events in the cell. The process starts with the binding of the extracellular chemical messenger, or ligand, to a receptor on the cell's plasma membrane. This binding activates the receptor, which then triggers a signaling pathway or cascade, involving various proteins and second messengers, to transmit the signal to the cell's interior. Finally, the signal leads to a specific cellular response, such as changes in gene expression, metabolism, or cell growth.