Answer: G 0 phase (quiescent state).
- A G<sub>1</sub> phase, preparing for DNA synthesis
- B S phase, during DNA synthesis
- C G<sub>0</sub> phase (quiescent state)
- D G<sub>2</sub> phase, preparing for mitosis
Correct answer: C. G<sub>0</sub> phase (quiescent state)
Explanation: G<sub>0</sub> phase: cells exit the cell cycle and enter a quiescent state. Many differentiated cells (neurons, muscle) are in G<sub>0</sub>.
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.