Which phase includes the final preparation before mitosis, including checks for DNA errors and centrosome formation?

• A. G2 phase
• B. G1 phase
• C. S phase
• D. Cytokinesis

Answer: (A)

Before a cell enters mitosis, it performs final readiness checks during the phase after DNA replication. This period, occurring after the genome has been duplicated, is when the cell verifies that the DNA is intact and repaired any minor errors before division. It also completes the preparation of the centrosomes so the spindle apparatus can form correctly for chromosome separation. If DNA damage is detected, the cell can pause to fix it, preventing the propagation of mutations. This phase is distinct from the earlier growth and nutrient-sensing stage, the DNA replication stage, and the actual division of the cytoplasm that follows mitosis.