CELL DIVISIONMITOSIS

DNA DNADNA

DNA

DNA

DNA

DNA

Objectives:

• At the end of this class, students should be able to:

• Describe the 4 stages of mitotic cell division• Explain the behaviour of the

chromosomes at each stage• Describe the cytokinesis process• Compare the cell division in animal

and plant• State the significance of mitosis

MITOSISdefinition

A type of nuclear division

followed up by the ___________ and

produces _____ daughter cells, each cell containing the same number of chromosome as parent cell

MITOSISthe phases

• Two phases of mitosis:

• _______________– the division/separation of nucleus

• _______________– the division of cytoplasm

MITOSISthe stages

• Karyokinesis

–___________–Metaphase–___________–Telophase

PROPHASE METAPHASE

ANAPHASE TELOPHASE

PROMETAPHASE

Chromosomes have been _____________.

In the form of chromatin fibers

The nuclear envelope dis____________.

During interphaseDuring interphase

Prophase

Chromatin condense

Spindle fibers

Nucleoli disappear

KARYOKINESIS

• Chromosome _______ / condense

• __________ disappear• Nuclear envelope

disintegrates• Spindle fiber begin

to form• Radial array of

shorter microtubules extend from centrosomes = “_________”

Metaphase

Centriole(poles)

KARYOKINESIS

• chromosome arrange on ____________ plate

• Centrosomes are at __________ poles of the cell

• Microtubules from each pole attach to the ____________ of the same chromosome

Anaphase

Centriole(poles)

KARYOKINESIS

• the chromosome /sister chromatid _____________.

• And __________ to the opposite poles

• The separated chromatids now called chromosomes

• Both poles have equivalent number of chromosomes

Telophase KARYOKINESIS

• Chromosomes distributed to ___________ poles of the cells

• Chromosome less tightly coiled & lengthen (in the from of chromatin)

• Nucleoli and nuclear envelope re-form

• ______________ begins

MITOSIScytokinesis

• Cell __________.• The process where one cell splits off from its

sister cell• The ____________ is divided after mitosis

In animal cells

• _________ _______ formed on the cell surface near the old metaphase plate

• Cell membrane ___________ forming furrow that’ll join up and splits the cell into two

CYTOKINESIS

In plant cells

• Vesicle derived from Golgi body move along the microtubule to middle of cell

• The vesicle fuse to form _______ ________.

• The contents of the vesicles used to form the new cell walls of the daughter cell

CYTOKINESIS

In plant cells

• The cell plate enlarges until its surrounding membrane fuses with the plasma membrane

• Two daughter cell form

CYTOKINESIS

Comparison the cell division in animal and plant

Plant Cell Animal Cell

THE SIGNIFICANCE OF MITOSIS• To facilitate ________ and cell

replacement– Increase number of cells within an

organism– Replace die or damage cells

• To facilitate ___________ reproduction– Bacteria, _________, Paramecium and

Euglena reproduce by binary fission

THE SIGNIFICANCE OF MITOSIS• To maintain the genetic

__________.– Produce 2 daughter cells that

posssess identical number of chromosomes to each other & to parent cell

List four phases of mitosis in correct order

Anaphase, Telophase, Metaphase and ProphaseMetaphase, Telophase, Prophase and AnaphaseProphase, Metaphase, Anaphase and TelophaseProphase, Anaphase, Telophase and Metaphase

ABCD

Centromeres split during

prophaseanaphasemetaphasetelophase

ABCD

Cytokinesis in animal cell division involves

Formation of new cytoplasm

Formation of cell plateFormation of two identical parts of cytoplasmPreparation of chromatin to condense

ABCD

Conclusion….

• Four stages of the mitotic cell division

– Prophase, – metaphase, – anaphase and – telophase

Conclusion…. • Cytokinesis – Plant

– Animal cell