Interphase is the longest phase in cell cycle. Interphase comprises of first growth phase or G1 phase, synthesis or S phase and second growth phase or G2 phase. Interphase is the phase of intense biochemical activity and prepares the cell for division.
Three major processes during interphase are (a) replication of DNA and synthesis of nuclear proteins (b) duplication of centriole in animal cells (c) synthesis of energy rich compounds.