Phases of Cell Cycle

The diagram of cell cycle phases shows its various phases inlcuding G1, S, G2, and M. The eukaryotic cell cycle is typically categorized into two primary phases:

Interphase

During interphase, the cell prepares itself for division by growing, replicating its DNA, and synthesizing necessary proteins. It is further divided into:

• G1 Phase (Gap 1): This phase follows cell division and represents the period of growth and preparation for DNA replication. During G1, the cell synthesizes proteins, RNA, and other molecules necessary for cell growth and function. The duration of G1 can vary greatly among different cell types and environmental conditions.
• S Phase (Synthesis): The S phase is characterized by DNA synthesis, where the cell’s genetic material is replicated. Each chromosome is duplicated, resulting in the formation of sister chromatids, which are held together at the centromere. Replication occurs in a semi-conservative manner, ensuring that each daughter cell receives an identical copy of the genetic material.
• G2 Phase (Gap 2): Following DNA replication, cells enter the G2 phase, which is marked by further growth and preparation for cell division. The cell continues to synthesize proteins, RNA, and organelles to support the upcoming division.

Also Read: Cell Cycle – Definition, Phases of Cell Cycle

Mitotic (M) Phase

The M phase is the last phase of the cell cycle and consists of two main processes: mitosis and cytokinesis. Mitosis is divided into several sub-phases: prophase, prometaphase, metaphase, anaphase, and telophase.

• Prophase: Chromatin condenses into visible chromosomes, the nuclear envelope breaks down, and spindle fibers begin to form.
• Prometaphase: Chromosomes become fully condensed, and microtubules of the mitotic spindle attach to the kinetochores of the chromosomes.
• Metaphase: Chromosomes align along the metaphase plate at the center of the cell.
• Anaphase: Sister chromatids separate and move towards opposite poles of the cell, pulled by the spindle fibers.
• Telophase: Chromosomes decondense, nuclear envelopes reassemble around each set of chromosomes, and the mitotic spindle breaks down.

Cytokinesis follows mitosis and involves the physical division of the cytoplasm to produce two daughter cells. In animal cells, cytokinesis typically involves the formation of a cleavage furrow, while in plant cells, a cell plate forms to divide the cytoplasm.

Also Read: Mitosis Cell Division: Definition, Stages and Diagram

The diagram of cell cycle provides insight into the essential process that all cells undergo to grow, replicate, and generate new cells. A cell cycle showcases a continuous sequence crucial for maintaining organism function and growth. The diagram of cell cycle class 11 is an important diagram which is often asked in the examination.

The cell cycle phases include Interphase and M-phase, where Interphase focuses on cell growth, DNA replication, and division preparation, while M-phase, or Mitosis, involves chromosome distribution to daughter cells.

The diagram of cell cycle labeled is given below: