What is the Difference Between G1 G2 and S Phase?

The cell cycle is composed of interphase (G1, S, and G2 phases) and the mitotic phase (mitosis and cytokinesis), which together lead to the formation of two daughter cells. The main differences between the G1, G2, and S phases are as follows:

• G1 Phase: This is the first growth phase, during which the cell grows by copying organelles and making molecular building blocks. The cell decides whether to proceed with the rest of the phases of the cell cycle or leave the cell cycle and enter a resting state called G0 phase.
• S Phase: This is the synthesis phase, where the cell replicates its DNA. The DNA is duplicated, and each chromosome now has two identical sister chromatids. The S phase is the second-longest phase of the interphase.
• G2 Phase: This is the second growth phase, during which the cell makes proteins and organelles, and begins to reorganize its contents in preparation for mitosis. The G2 phase is the shortest phase of the interphase.

In summary, the G1 phase is focused on cell growth, the S phase is dedicated to DNA synthesis, and the G2 phase is about cell division preparation.

Comparative Table: G1 G2 vs S Phase

The cell cycle consists of different phases, including G1, S, and G2, which together make up interphase. Here is a table summarizing the main differences between G1, G2, and S phases:

During the G1 phase, cells focus on growing and synthesizing proteins. In the S phase, cells replicate their DNA, creating two identical sister chromatids for each chromosome. The G2 phase is the final preparation for mitosis, where cells may undergo additional growth and produce more organelles.