When does DNA replication take place in the cycle?
DNA replication takes place during the S phase (synthesis phase) of the cell cycle. To understand this, let's break it down:
1. The cell cycle: The cell cycle is a series of ordered events that a cell goes through from its formation to cell division. It consists of four main phases - G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis or cell division).
2. S phase: The S phase is the phase of the cell cycle where DNA replication occurs. During this phase, the DNA molecules in the cell's nucleus are duplicated, resulting in two identical copies. This process is essential for cell division, as each new cell needs a complete set of genetic information.
3. G1 and G2 phases: Before and after the S phase, there are the G1 and G2 phases. During the G1 phase, the cell grows, carries out its normal functions, and prepares for DNA replication. After the S phase, during the G2 phase, the cell continues to grow and prepare for cell division.
So, in summary, DNA replication takes place during the S phase of the cell cycle.