During which phase does most of a cell’s growth occur?

• A. Mitosis
• B. S phase
• C. G1 phase
• D. G0 phase

Answer: (C)

In this phase, the cell’s growth is most pronounced. During G1, the cell increases in size and actively manufactures proteins, lipids, and organelles to build up the cytoplasm and prepare for DNA replication. This is when the cell ramps up metabolic activity and mass to reach a suitable size for the upcoming S phase.

In contrast, S phase is focused on copying the genetic material, not increasing cell size. G2 continues growth but mainly to finish preparing for mitosis and to accumulate energy and components needed for division. Mitosis is cell division, so growth isn’t occurring there. G0 is a resting state where the cell isn’t actively growing or dividing.

So, most growth happens during G1.