The mitotic phase is a relatively short period of the cell cycle. It alternates with the much longer interphase, where the cell prepares itself for cell division. Interphase is therefore not part of mitosis. Interphase is divided into three phases, G1 (first gap), S (Synthesis), and G2 (second gap). During all three phases, the cell grows by producing proteins and cytoplasmic organelles. However, chromosomes are replicated only during S-phase. Thus, a cell grows (G1), continues to grow as it duplicates its chromosomes (S), grows more and prepares for mitosis (g2) and finally it divides (M) before restarting the cycle.