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At the end of this lesson, students are able to: MITOSIS At the end of this lesson, students are able to: Understanding mitosis Draw and label the phases of mitosis Identify the changes occur in each phase State the functions of mitosis in cell organism

MITOSIS Prophase Metaphase Anaphase Telophase Is the process in which a parent cell divide and produce two daughter cells that are genetically to the parent cell. 4 stages Prophase Metaphase Anaphase Telophase

Cell Cycle 90% of the cell cycle is in interphase, other 10% is mitosis (cellular division) Interphase composed of 3 phases: G1, S, and G2 G1 (Gap 1) phase: cellular growth and protein synthesis, in preparation for the S phase S (Synthesis) phase: DNA synthesis/replication of each chromosome in the cell, forms sister chromatids. G2 (Gap 2) phase: cellular growth as well as protein & lipid synthesis, in preparation for mitosis Ex. Synthesis of proteins used to form mitotic spindle

Phases of Mitosis: (PMAT) + cytokinesis Prophase: chromosomes become visible, begin to condense, attach to spindle Metaphase: chromosomes line up at metaphase plate/equatorial plane Anaphase: sister chromatids separate by kinetochores Telophase: two daughter nuclei reform at the 2 poles -Cytokinesis (division of the cytoplasm) occurs simultaneously

ANIMAL CELL

PROPHASE 1 Chromosomes in the nucleus condense and become more tightly coiled. The sister chromatids which are held together at centromere become visible. At the cytolaplasm, spindle fiber begin to form and extend between the centrioles. End of this phase, the nucleolus disappear and the nuclear membrane disintegrates.

METAPHASE 2 Centromere of all chromosomes are lined up on the metaphase plate. The two sister chromatids are still attached to one another at the centromere. Metaphase end when the centromeres divide

3 ANAPHASE Centromere divides into two. Chromatid sisters separated and move towards the opposite poles of the cell. End of this stage, chromosomes reach the poles.

4 TELOPHASE Chromosomes begin uncoil. The formation of nuclear membrane. The chromosomes become less visible under the microscope. The spindle fibers disappear and a new nuclear membrane form around each set of chromosomes. The two daughter nuclei formed. Hence, completed the process of mitosis

CYTOKINESIS CYTOKINESIS Is the division of cytolplasm. Animal cell Begins when the cell membrane contracts due to the interaction of myosin and actin microfilaments at the cell membrane forming cleavage furrow. Furrow cleavage continues until two daughter cells are completely separated. Plant cell Vesicle forming a cell plate. The cell fuses to form new cell walls and plasma membranes. Two daughter cells are formed at the end of cytokinesis.

IMPORTANCE OF MITOSIS Growth Reproduction Maintaining Repairing Increase number of cells, Contribute the growth of tissue and organs of multicellular organism Growth Some of the organism reproduce asexually by mitosis. Ex: paramecium, euglena and plants Reproduction Maintain the same number of chromosomes as the parent cell and genetically similar to the parent cell Maintaining Repair worn out and damaged tissue Repairing

Mitosis is the process of cell division from a parent cell forming two daughter cells, identically to the parent Stages in mitosis process Interphase (G1, S, G2) Prophase Metaphase Anaphase Telophase The process completed the separation of cytoplasm is cytokinesis. Importance of mitosis are in growth, reproduction, repairing and maintaining cells CONCLUSION

Extra Credit Activity Mitosis through edible modeling -All stages of mitosis need to be represented (PMAT+cytokinesis) -Each stage should have a notecard identifying the stage and labeling what is happening. After presentation to the class (and possible photograph) of project, it may be disposed of as you see fit.