Question

DNA replication occurs during which part of the cell cycle?

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

Answer 1

The correct option is A

S phase

The phases of the cell cycle are interphase, G0, G1, S phase, G2 and M phase. DNA replication occurs during the S phase.

During the G1 phase, the cell chooses either to replicate its deoxyribonucleic acid (DNA) or to exit the cell cycle and enter a quiescent state (the G0 phase).

The portion of interphase which follows the S phase is called the G2 phase. Some cells can exit the cell cycle from the G2 phase, just as they can from the G1 phase.