Question

fill in the blank question
a second messenger system activates an enzyme , which increases the intracellular response by a thousandfold.

Explanation:

In second - messenger systems, adenylate cyclase is an enzyme that can amplify the intracellular response. It converts ATP to cyclic AMP (cAMP), and a small amount of extracellular signal can lead to a large number of cAMP molecules being produced, increasing the intracellular response by a thousandfold or more.

Answer:

adenylate cyclase