Final answer:
Before mitosis, a cell goes through interphase, which includes the G1 phase where the cell grows and gathers resources, the S phase where DNA replication occurs, and the G2 phase where further growth and preparation for mitosis take place.
Step-by-step explanation:
What Happens in Interphase Before Mitosis?
Before a cell enters mitosis from interphase, it goes through several critical stages of preparation. Interphase includes three main phases known as G1, S, and G2.
G1 Phase (First Gap)
In the G1 phase, the cell grows and carries out its normal functions while also preparing for the next stage by accumulating necessary proteins and energy reserves. This phase is characterized by substantial biochemical activity despite microscopic changes not being distinctly visible.
S Phase (Synthesis of DNA)
The S phase is marked by DNA replication, where the cell duplicates its chromosomal DNA, ensuring that each new cell will have an identical set of DNA after the cell division. Replication of DNA is crucial because it allows each daughter cell to have a complete set of genetic instructions.
G2 Phase
Following DNA synthesis, the cell enters the G2 phase where it continues to grow and begins to form proteins and other structures needed for mitosis. At the end of the G2 phase, the cell checks for DNA damage and ensures all proteins necessary for cell division are present.