Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: The effects of extracellular signals can also be amplified by enzymatic cascades. At the initiation of the signal, a single ligand binds to a single receptor. However, activation of a receptor-linked enzyme can activate many copies of a component of the signaling cascade, which amplifies the signal. Answer: enzymatic cascades
A:
What helps amplify the effects of extracellular signals?