During interphase, the cell grows and carries out various metabolic processes. There are three main stages of Interphase:G1 - During the gap1 phase the cell assimilates new material, grows and develops. This can take hours, days, months or years.S - When the cell divides half the genetic material goes to each cell, so the DNA must be doubled to maintain the same amount of genetic material. DNA replication occurs during this phase. Each strand is copied so the chromosomes are now made of two identical chromatids held together by a centromere.G2 - During the gap2 phase, organelles such as mitochondria and proteins and ATP needed for cell division are synthesised. Prior to mitosis, the nucleus consists of loosely coiled chromatin - DNA strands loosely wound round histone proteins. Individual chromosomes cannot yet be seen.