Mitosis Seminar Presentation

1. MITOSIS
Anila M R
First Semester
Natural Science

2. INTRODUCTION
Cell cycle has mainly two phases namely Interphase (Preparatory phase)
and Division phase.Major events involved in Interphase are :-
 Number of cell organelles increased.
 Increase in the quantity of cytoplasm.
 Increase in cell size.
 Genetic material duplicates.
Division phase consists of nuclear division and cytoplasmic division.The
cell attain complete growth during Interphase. These cells undergoes
division and becomes daughter cells . As the interphase and division phase
repeats in a cyclic manner , they together constitute the cell cycle .There
are manily two types of cell division - Mitosis and Meiosis .Division of
somatic cells are called Mitosis . Division of germ cells are called Meiosis .

4. MITOSIS
Mitosis is a type of cell division in which a mother
cell divides into two daughter cells. During mitosis ,
division of nucleus and cytoplasm takesplaces.
Division of nucleus is known as Karyokinesis and
division of cytoplasm is known as Cytokinesis .
Karyokinesis is completed in four phases namely
Prophase , Metaphase , Anaphase , Telophase .
Cytokinesis occurs after the completion of
telophase .

6. Prophase :-
Condensation of chromosomes
tookplace. Nuclear membrane and cell organelles
disappears . Spindle fibres are formed . In plant cells ,
as the centrosomes are absent , spindle fibres are
formed without centrioles .

7. Metaphase:-
Chromosomes are aligned at the
equator of the spindle ( Metaphase Plate).

8. Anaphase :-
The sister chromatids separates and move
towards opposite poles.

9.  Telophase :-
Formation of two daughter nuclei . Nuclear
envelope and cell organelles reappears.
Telophase is followed by Cytokinesis which leads to form two
daughter cells. This marks the completion of cell division.
Cytokinesis in animal cells are indicated by the invagination of
plasma membrane at the centre of the cell. Cytokinesis in
plant cells are indicated by the formation of small vesicles
between the daughter nuclei. These vesicles joined together
to form cell plates . These cell plates extends to both sides
and joined with the plasma membrane .

11. CONCLUSION
Mitosis is a controlled process and it is responsible for
the growth and development of the individual. Mitosis
also ensures the uniqueness and continuity of an
organism. Mitosis helps in repair and regeneration of
damaged tissues. Any distruption in the equilibrium of
mitosis leads to excessive division of cells and its
proliferation. This leads to disease like cancer .
Similarily an unbalanced growth and development of
society leads to the destruction of environment and
causes natural calamities .

12. REFERENCE