[Campbell Biology P.296] According to the text, what is the immediate enzymatic action trigg... | Practice Question

According to the text, what is the immediate enzymatic action triggered by the activation of the regulatory protein complex at the M checkpoint, which directly leads to sister chromatid separation?

  • A: Cleavage of cohesins by separase
  • B: Attachment of kinetochores to spindle fibers
  • C: Phosphorylation of Cdk proteins
  • D: Synthesis of new spindle fibers

Explanation

The text states: "Once activated, the complex sets off a chain of molecular events that activates the enzyme separase, which cleaves the cohesins, allowing the sister chromatids to separate." Therefore, the immediate enzymatic action is the cleavage of cohesins by separase.