📚 StudyHub

🔬 Biology  ·  Cell Cycle and Cell Division  ·  NEET

Securin prevents premature sister chromatid separation by:

  • A Forming a direct physical bridge between sister chromatids
  • B Inhibiting separase (which would cleave cohesin)
  • C Nucleating spindle microtubules at the centrosome
  • D Adding phosphate groups onto condensin II subunits

Correct answer: B. Inhibiting separase (which would cleave cohesin)

Explanation: Securin inhibits separase. At anaphase onset, APC/C degrades securin, freeing separase to cleave cohesin Scc1 subunit, triggering sister chromatid separation.

Concept context

Mitosis and meiosis: how cells divide for growth, repair, and reproduction.

Read the full Cell Cycle and Cell Division notes →