describe what is occuring in each stage of interphase (G1, S, G2)
During interphase, a cell prepares for cell division by growing, replicating DNA, and synthesizing proteins. Interphase is divided into three stages: G1, S, and G2.
1. G1 phase: In this phase, the cell grows and carries out its normal functions. It accumulates energy stores and increases its size. The main objective is to prepare the cell for DNA replication in the S phase. The G1 phase is a critical checkpoint for the cell to ensure it is ready to proceed with the cell cycle.
2. S phase: The S phase stands for the synthesis phase. It is during this stage that the DNA in the cell is replicated or synthesized. The cell's DNA content doubles as each chromosome is duplicated to ensure that each daughter cell produced will have an exact copy of the genetic material. Moreover, proteins associated with DNA, such as histones, are also synthesized during this phase.
3. G2 phase: In the G2 phase, the cell continues to grow and prepare for cell division. It checks its DNA for errors and ensures that DNA replication has been accurately completed during the S phase. Additionally, the cell synthesizes proteins required for mitosis, such as those involved in spindle formation and cell division. The G2 phase acts as another crucial checkpoint to ensure the cell is ready to enter the next phase of the cell cycle, mitosis.