20090824100844 Simulation Assignment

CELL DIVISION Mitosis in Animal Cell Mitosis is a process of cell division which results in the production of two daughter cells from a single parent cell. The daughter cells are identical to one another and to the original parent cell. In a typical animal cell, mitosis can be divided into four principals stages: •

Prophase: The chromatin, diffuse in interphase, condenses into chromosomes. Each chromosome has duplicated and now consists of two sister chromatids. At the end of prophase, the nuclear envelope breaks down into vesicles.

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Metaphase: The chromosomes align at the equitorial plate and are held in place by microtubules attached to the mitotic spindle and to part of the centromere.

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Anaphase: The centromeres divide. Sister chromatids separate and move toward the corresponding poles.

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Telophase: Daughter chromosomes arrive at the poles and the microtubules disappear. The condensed chromatin expands and the nuclear envelope reappears. The cytoplasm divides, the cell membrane pinches inward ultimately producing two daughter cells (phase: Cytokinesis).

ENGAGE

IN THE WOMB You are given the picture as shown below:

1. What do you observe? 2.

How the foetus develop?

3. What is the main process that occurs during fetus development?

EMPOWER STEPS 1. Mitosis is the type of cell division that produces new cell for growth and to replace old cell that damaged or dead. 2. There are four main phases of mitosis:

3.

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Prophase

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Metaphase

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Anaphase

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Telophase

Log on the web side and observe the animation to answer the question. http://www.cellsalive.com/mitosis.htm

RESULT

Interphase

Prophase

Metaphase

Anaphase

Telophase

Cytokinesis

Questions 1. What is the role of mitosis in living organisms 2. How mutation occurs during mitosis? 3. Explain the example of mitosis application. Answers: 1. Mitosis is important to maintain the diploid chromosome number in the cell. This is ensure that chromosome number during sexual reproduction is remain from generation to the next generation. 2. Mutation of the cell is due to mistake in replication of DNA as cell repair to divide, damage to the DNA by radioactive and carcinogenic substances and destruction to the orderly movement of chromosomes during cell division. 3. (i) Cloning in plant : tissue culture is the process of growing cell artificially in the laboratory that produces genetically identical clone. (ii) Cloning of animal : reproductive cloning that produces and entire animal that is genetically identical to parent animal. While therapeutic cloning apart of person (skin, heart, liver) are duplicated to produce a clone in the treatment of disease

ENHANCE The diagram shows phases of mitosis of a plant cell in incorrect order

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4

2 5

3

6

1. Based on the diagram, match the following figure with the correct statements. A Chromosomes completely arrive at the poles. _______________________ B Nuclear membrane disappear. _________________________ C. Paired centriol move to opposite ends of the cell ._____________________ D.Synthesis of new organelles, synthesis of protein and chromosome. ___________________ E. Sister chromatids line up at the spindle equator. ___________________ F. Chromatid condense and become visible under light microscope observation. _____________________

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G. Cell is ready for cytokinesis.________________________