in an epinephrine-triggered signal transduction pathway, how would cellular response most likely be affected if epinephrine could not bind with the receptor protein? g proteins would remain inactive and prevent signal amplification from occurring. non-specific signaling would occur, and epinephrine would bind to different receptors. signal amplification would occur in the extracellular fluid rather than inside the cell. the cell could not receive termination signals and carry out inactivation.