The cell cycle is the repeating series of steps a cell goes through as it grows and then divides into two new cells.

What is the cell cycle?

In simple terms, the cell cycle is a control system that makes sure a cell copies everything it needs (especially its DNA) and then splits accurately into two daughter cells. It is crucial for growth, healing wounds, and replacing worn‑out cells in your body.

One full cell cycle = start as one cell → grow → copy DNA → divide into two new cells.

Main stages (big picture)

Biologists usually split the cycle into two big parts.

  • Interphase (the “life and prep” phase).
  • M phase (mitosis and cytokinesis, the actual division).

During interphase, the cell is doing normal work, growing, and copying its DNA. During M phase, it shares the copied DNA into two nuclei (mitosis) and then splits the cell in two (cytokinesis).

Interphase: G1, S, G2

Interphase has three sub‑phases.

  1. G1 phase (Gap 1)
    • Cell grows in size and makes lots of proteins and organelles.
 * It’s like stocking up and checking systems before copying DNA.
  1. S phase (Synthesis)
    • The cell copies its DNA so each future daughter cell can get a full set of chromosomes.
 * This is the phase where the genome is duplicated.
  1. G2 phase (Gap 2)
    • The cell does more growth and final checks, repairing DNA damage and preparing machinery for mitosis.
 * There is a G2 “checkpoint” that makes sure everything is ready for division.

Some cells can exit the active cycle into a resting‑like state called G0, where they stop dividing for a while or long term.

M phase: mitosis and cytokinesis

M phase is when the cell actually divides.

  • Mitosis
    • The nucleus divides and the duplicated chromosomes are separated into two identical sets.
* Classic mitosis is described in stages (prophase, metaphase, anaphase, telophase) where chromosomes condense, line up, split, and move to opposite sides of the cell.
  • Cytokinesis
    • The cell’s cytoplasm and membrane pinch in two, forming two daughter cells, each with its own nucleus.
* After cytokinesis, each daughter cell can enter a new G1 phase and the cycle repeats.

Checkpoints and control (why it matters)

The cell cycle has built‑in “checkpoints” that act like quality‑control stops.

  • G1 checkpoint: Is the cell big enough, and is the DNA okay before copying?
  • G2 checkpoint: Was DNA replication completed correctly and is the cell ready for mitosis?
  • Metaphase (spindle) checkpoint: Are all chromosomes properly attached and lined up before they are pulled apart?

These controls help prevent damaged or incorrect cells from dividing, and when they fail, it can contribute to diseases like cancer.

Quick recap (TL;DR)

  • The cell cycle is the ordered set of steps a cell follows to grow and divide into two daughter cells.
  • It has growth and DNA‑copying phases (G1, S, G2) grouped as interphase, plus a division phase (M) that includes mitosis and cytokinesis.
  • Checkpoints throughout the cycle keep the process accurate and safe.

Bottom note: Information gathered from public forums or data available on the internet and portrayed here.