Question

during which step of the cell cycle is dna checked for errors following dna replication? a. g₁ checkpoint b. s phase c. mitosis d. g₂ checkpoint

Explanation:

• G₁ checkpoint: Checks for cell size, nutrients, growth factors, and DNA damage before the cell enters the S phase (DNA replication phase). It is not related to checking DNA after replication.
• S phase: This is the phase where DNA replication occurs. It is not a checkpoint for error - checking after replication.
• Mitosis: It is the process of cell division (nuclear division). It is not a checkpoint for DNA errors after replication.
• G₂ checkpoint: After DNA replication in the S phase, the G₂ checkpoint checks for DNA damage and completeness of DNA replication. If there are errors, the cell cycle can be arrested here for DNA repair.

Answer:

D. G₂ checkpoint