CELL DIVISION & CELL CYCLE – THE CONTINUATION OF LIFE
Life on the earth is due to Cell division & cell cycle. Different phases of Cell division & Cell Cycle are described below:
·      The earth is teeming with countless living cells.Â
·      You have 100 trillion cells in your body alone.
·      They are …. you.
·      Cell comes in all sizes and shapes.Â
·      They perform thousands of different tasks in the life forms of earth.
·      They work together to form the tissues of all living things.
·      But cell don’t live forever. Eventually they die.
·  Fortunately, they have ability to reproduce through a process called cell division.
·    It begins a chemical signal to prepare for reproduction. The cell grows larger. It is called “G1 Phase” of cell’s life.
·      After growth, the cell duplicates it s DNA. This is called the “S Phase” of the cell cycle.
·    The DNA is then checked by enzymes for mistakes & repaired. This is “G2 Phase” of cell cycle.
·  When ready cell division begins . It is called “Mitosis” and the cell division.
· Mitosis begins when the nuclear membrane dissolves and DNA thickens called (Prophase).
·   Special fibers called spindle fibers form on each end of the cell and grow towards the DNA chromosomes.
·   The fiver then attach to centromeres on the chromosomes and pull them into a line in the middle of the cell called (Metaphase).
·  The chromosomes are pulled apart by the spindle fibers to opposite sides of the cell called (Anaphase).
·   Lase is Telophase. Two new nuclei form the cell and then divides in two called Cytokines.
·      all of us started life as single cell that divided again and again.
·      But the first cell experienced something special… SEX.
·      The cells involved in SEX are produced by a process called Meiosis.
·    Cell division & cell cycle – the continuation of life.
