Eleven Standard >> Cell cycle

Cell cycle

Definition of the Cell Cycle:
The cell cycle refers to the series of events that occur in a cell leading to its growth, replication of genetic material, and division into two daughter cells. It encompasses the stages through which a cell progresses, ensuring proper growth and maintenance of living organisms.

Phases of the Cell Cycle:

Interphase:

G1 Phase (Gap 1): The cell grows and carries out its normal functions. It prepares for DNA replication by synthesizing proteins and accumulating energy.
S Phase (Synthesis): DNA replication occurs, resulting in the duplication of the cell's genetic material. Each chromosome forms a sister chromatid, connected at the centromere.
G2 Phase (Gap 2): The cell continues to grow, synthesizes proteins, and prepares for cell division. It checks DNA for errors, repairs any damage, and ensures proper replication.
Mitotic Phase (M Phase):

Mitosis: The nucleus of the cell divides, ensuring each daughter cell receives an identical set of chromosomes.
Prophase: Chromosomes condense, becoming visible structures. The nuclear envelope breaks down, and spindle fibers begin to form.
Metaphase: Chromosomes align along the equatorial plane (metaphase plate) of the cell.
Anaphase: Sister chromatids separate and move towards opposite poles of the cell, pulled by spindle fibers.
Telophase: Chromosomes arrive at the poles. Nuclear envelopes re-form around each set of chromosomes, and the spindle fibers disassemble. Chromosomes begin to decondense.
Cytokinesis: The division of the cytoplasm and organelles to form two daughter cells.
In animal cells: A cleavage furrow forms, which deepens until the cell is pinched into two separate cells.
In plant cells: A cell plate, consisting of vesicles containing cell wall material, forms at the equator. The cell plate gradually develops into a new cell wall that separates the daughter cells.