What key event occurs during Interphase of mitosis?

During Interphase of mitosis, the key event is the copying of DNA, which is essential for cell division. Interphase is the stage where the cell prepares for mitosis and is divided into three phases: G1 (Gap 1), S (Synthesis), and G2 (Gap 2).

In the S phase, DNA replication occurs, resulting in two identical copies of each chromosome, known as sister chromatids. This duplication is crucial because, in the subsequent phases of mitosis, each daughter cell needs to receive an exact copy of the genetic material.

By the end of Interphase, the cell has doubled its genetic material and has also increased in size and synthesized other components necessary for cell division. This preparation is vital to ensure that the mitotic process can proceed smoothly, leading to successful division into two daughter cells with the correct amount of DNA.