Complex sentence: Once the alpha subunit of the G s protein is released, it activates the enzyme named adenylyl cyclase whose function is to convert ATP into cAMP by a cyclization process.
Split into simpler sentences: Once the alpha subunit of the Gs protein is activates, it activates the enzyme named Adenylyl cyclase. Adenylyl cyclase is an enzyme whose function is to convert ATP into cAMP by a cyclization process.