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The CELL CYCLE and MITOSIS PowerPoint Presentation
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The CELL CYCLE and MITOSIS

The CELL CYCLE and MITOSIS

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The CELL CYCLE and MITOSIS

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  1. The CELL CYCLE and MITOSIS

  2. DNA IS ENCODES OUR GENETIC BLUEPRINT DNA IS PACKAGED INTO CHROMOSOMES RESULT: DNA MOLECULE IS PACKAGED INTO A CHROMOSOMES THAT IS 50,000X SHORTER THAN ITS EXTENDED LENGTH

  3. SEM of chromosomes (d/s)

  4. single stranded (s/s) chromosome double stranded (d/s) chromosome Chromosome structure centomere Chromatid

  5. DNA Replication

  6. Introducing the cell cycle Introduction to cell cylce Details of the Cell cycle and Mitosis

  7. The cell cycle Enters own cell cycle Enters own cell cycle May exit from cell cycle: Ageing and differentiation pathway

  8. Stages of Mitosis: • Use the matching cards to form a table in the format shown on the next slide: • Finish the table in your notes by completing the description of each phase and then drawing a simple diagram of each phase.

  9. Real images: Stages of Mitosis A C D B

  10. Cross Section Showing Cells in various stages of the cell cycle.

  11. Now complete the activity Online garlic root tips: webaddress and question on work sheet.http://www.biology.arizona.edu/cell_bio/activities/cell_cycle/cell_cycle.html

  12. Read 79-83 qu 9-14Additional slides that might help answer question that crop up

  13. DNA IS ENCODES OUR GENETIC BLUEPRINT DNA IS PACKAGED INTO CHROMOSOMES RESULT: DNA MOLECULE IS PACKAGED INTO A CHROMOSOMES THAT IS 50,000X SHORTER THAN ITS EXTENDED LENGTH

  14. SEM of chromosomes (d/s)

  15. single stranded (s/s) chromosome double stranded (d/s) chromosome Chromosome structure centomere Chromatid

  16. DNA Replication

  17. Mitosis in garlic root tip

  18. If cells are overlapping, squash the slide again. Avoid moving the coverslip from side to side. n Make sketches of (or take photographs of) cells that show any of the stages of mitosis. o Calculate the mitotic index. p Compare the mitotic index of root tips from alliums that have been sprouting for 1, 2, 5 and 10 days. q If available, compare the allium meristem tissue with that from other species. Teaching notes Cell division in flowering plants takes place in particular regions of the plant called meristems. Cells in meristems are not specialized for any particular function and divide repeatedly by mitosis. Some of the daughter cells remain meristematic; others cease dividing and become differentiated into appropriate cell types depending on their position. The root tip meristem is usually a denser white and more rounded than the cut end. Chromosomes in root tip tissue are made visible with the stain. Dividing cells (if present) will show up clearly with chromosomes in different forms according to the stage of mitosis. Individual chromosomes (as tightly-coiled threads) are visible during anaphase. The links between the cellulose walls of plant cells are broken down by the treatment with hydrochloric acid. This ensures that the stain can penetrate the cells and allows the tissue to be squashed out one cell thick. The mitotic index is calculated like this: The duration of each stage of mitosis has been recorded and the data (see table below) could be used to compare the observed frequencies of the different stages as recorded by students.

  19. compare the observed frequencies of the different stages as recorded by students.