Phase of DNA Synthesis
DNA-synthesis occurs in which phase of cell division:
- S-phase — Correct Answer
- $G_{1}$-phase
- $G_{2}$-phase
- None
Explanation:
Correct Answer: S-phase
DNA replication (synthesis) occurs exclusively during the S-phase (Synthesis phase) of the cell cycle's interphase. This doubles the DNA content of the cell in preparation for division.
Phases of the Cell Cycle
| Phase | Sub-phase | Key Event |
|---|---|---|
| Interphase | G₁ phase (Gap 1) | Cell growth; preparation for DNA synthesis |
| S phase (Synthesis) | DNA replication — chromosome number doubles | |
| G₂ phase (Gap 2) | Preparation for mitosis; protein synthesis | |
| M phase | Mitosis / Meiosis | Cell division; chromosome separation |
Why Other Options Are Wrong
- G₁-phase: Cell grows and prepares, but no DNA synthesis occurs.
- G₂-phase: Post-replication; prepares for division, but replication is already complete.
📚 About this Topic — Animal Genetics & Breeding
This multiple choice question is from Animal Genetics & Breeding, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Genetics & Breeding to strengthen your preparation.
