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Bio cell cycle and cell division

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Page 1: Bio cell cycle and cell division
Page 2: Bio cell cycle and cell division

Sister chromatids of each chromosomes separate completely to become daughter chromosomes.

New chromosomes move towards the poles along the path of their spindle fibers

Centromeres lead the path and arms trail behind

Page 3: Bio cell cycle and cell division
Page 4: Bio cell cycle and cell division

Events occurring during anaphase

Centomeres split and chromatids separate

Chromatids move to opposite poles

Page 5: Bio cell cycle and cell division

Final stage of mitosis.

Chromosomes that have reached their respective poles decondense and lose their individuality.

Page 6: Bio cell cycle and cell division

Events occurring in telophase

Chromosomes cluster at opposite spindle poles and their identity is lost as discrete elements.

Nuclear envelope assembles around the chromosome cluster

Nucleolus, golgi complex, ER reform.

Page 7: Bio cell cycle and cell division

It is the division of cytoplasm of parent cell into two daughter cells

Page 8: Bio cell cycle and cell division

Cytokinesis in animal cells

In animal cell it is achieved by the appearance of a furrow in the plasma membraneThe furrow gradually deepens and ultimately joins the centre dividing the cell cytoplasm into two

Wall formation starts in the centre of the cell and grows outward to meet the existing lateral walls.

Page 9: Bio cell cycle and cell division

Cytokinesis in plant cells

Plant cells are enclosed by relatively inextensible cell wall.Therefore they undergo cytokinesis by a different mechanism.

Wall formation starts in the centre of the cell and grows outward to meet the existing lateral walls.

Formation of new cell wall begins with the formation o a simple precursor, called the cell plate that represents the middle lamellabetween the walls of two adj cells.

Page 10: Bio cell cycle and cell division
Page 11: Bio cell cycle and cell division

In some organisms karyokinesis is not followed by cytokinesis as a result of which multinucleate condition

arises leading to the formation of

syncytium

Page 12: Bio cell cycle and cell division

GROWTH: New somatic cells are formed by mitosis. Therefore, mitosis helps in growth and development of multicellular organisms

REPAIR: Repair of the body takes place because of the addition of cells by mitosis.The cells of the upper layer of the epidermis, cells of lining of the gut, and RBCs are constantly being replaced