Answer: Every kinetochore has tension from being attached to microtubules from opposite poles.
- A Every chromosome has largely condensed in preparation for upcoming division in typical laboratory settings
- B Every kinetochore has tension from being attached to microtubules from opposite poles
- C Cytokinesis has already begun and the cleavage furrow is actively forming under usual circumstances
- D DNA replication has largely completed across the entire genome sequence according to most researchers
Correct answer: B. Every kinetochore has tension from being attached to microtubules from opposite poles
Explanation: SAC is silenced only when ALL kinetochores have amphitelic (bioriented) attachments generating tension. Mad2 is released from kinetochores, allowing APC/C activation.
The cell cycle: G1 (growth and preparation), S (DNA replication, chromosome number stays 2n but DNA content doubles), G2 (final checks before division), and M (mitosis itself) - together, G1+S+G2 make up interphase.
Concept context
Mitosis and meiosis: how cells divide for growth, repair, and reproduction.