Which part of the cell cycle is the most variable G1 phase S

Which part of the cell cycle is the most variable? G_1 phase S phase G_2 phase M phase

Solution

Answer:

G1 phase:

G1 phase is the first phase of the cell cycle. It is the end of the previous Mitosis phase until the beginning of DNA replication is called G1 (G indicating gap). It is also called the growth phase. The biosynthetic activities of the cell had been considerably slowed down during M phase, but during G1 phase the actgivities are resumed at a high rate. This phase is marked by synthesis of various enzymes that are required in S phase, mainly those needed for DNA replication. Duration of G1 is highly variable, even among different cells of the same species.