Final answer:
Regulation of M-cdk activity is done through negative feedback inhibition in the cell cycle. Cdk inhibitors block the activation of Cdks until specific cell cycle events are completed.
Step-by-step explanation:
Regulation of M-cdk activity is done through negative feedback inhibition in the cell cycle. Molecules known as Cdk inhibitors prevent the full activation of Cdks, which are cyclin-dependent kinases. These inhibitors monitor specific cell cycle events and block the activation of Cdks until the event is completed. This feedback mechanism ensures that the cell cycle progresses smoothly and that problematic conditions are resolved before moving forward.