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Introduction to mitotic cell cycle:Multicellular organisms begin life as a single cell and go on to become more complex through acombination of cell division and differentiation. Even in adults cell division is constantly providing newcells to replace those that die.

What is Mitotic Cell Cycle?Mitosis is the process of normal cell division. In mitosis the chromosomes are copiedand then divided equally between the two new daughter cells. So each mitotic cell cycleproduces two cells, both diploid and each with exactly the same genes as the parentcell. Mitosis takes place in all the somatic cells of the body.

Mitosis is One of the Stages of Cell Cycle:Cell cycle is the complete sequence of events in the life of an individual diploid cell. Thecycle starts and ends with cell division and consists of the stages of mitosis plusinterphase, the interval between the divisions. Cells that do not divide are always ininterphase. The stages of cell cycle were:

Interphase or resting phase G1 phase or Growth phase 1 S phase or S ynthesis phase G2 phase or Growth phase 2 M phase or Mitotic phase

Mitotic Cell Cycle Type:Mitotic cell cycle is a continuous sequence of events that is divided into four distinct stages andcytokinesis:1) Prophase (pro= before)

Chromatin begins to condense into chromosomes

As the DNA has already replicated in S-phase , the chromosome has two sister chromatids joinedat centromere

The nucleolus begins to breakdown

The centrioles move to opposite side of the nucleus (centrioles are absent in plant cells)

Nucleolus disappears2) Metaphase (meta= middle)

Disappearance of nuclear membrane

Spindle becomes fully developed and fills the space that was occupied by the nucleus

The chromatid pairs attach themselves to individual spindle fibres and align themselves on theequator of the spindle.

3) Anaphase (ana= apart)

The chromatids are pulled apart by the movement of spindle fibres, so that the sister chromatidsare pulled to the opposite poles.

The newly separated chromatids are now called chromosomes and are single structures.4) Telophase (telo=final)

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The chromosomes reach the poles of the spindle

They then decondense and become indistinct, forming the chromatin like in interphase

The nuclear membrane reforms and nucleolus reappears

Cell resumes normal cytoplasmic functions

5) CytokinesisSplitting of the cell is called cytokinesis which starts at anaphase. In animal cells, microtubules form afurrow in a ring around the cell. These gradually constricts until the cells separate. In plants a cell plate isformed by the fusion of vesicles from golgi apparatus. These fused vesicles separate the daughter cells.

Significance of Mitotic Cell Cycle: It helps in growth and development of an organism.

It helps in replacement of worn out and dead cells.

Helps in differentiation during the development of zygote.