Name: ___________________________ Period: ____________ Date: _____________________ How Cells Divide: Meiosis Worksheet to accompany PBS Nova Animation http://www.pbs.org/wgbh/nova/baby/divide.html Step 1 – Before We Split 1. How many chromosomes are in the human genome? 2. How many chromosomes are in a sperm or egg cell 3. For each of the following diagrams, draw the chromosomes of the mother in one color and the chromosomes of the father in a different color. Key: Chromosomes from father = [ ] Chromosomes from mother = [ ] Draw the cell as it appears during this stage. Label the following parts: - Nuclear envelope - Nucleolus - Chromatin - Centrioles Step 2 – Interphase I 4. What replicates during this time? Draw the cell as it appears during this stage. Label the following parts: - Nuclear envelope - Nucleolus - Chromatin - Centrioles Written by James Dauray http://www.docstoc.com/profile/jamesdauray Page 1 Step 3 – Prophase I 5. What occurs during this stage of meiosis that does not occur during mitosis? Draw the cell as it appears during this stage. Label the following parts: - Nuclear envelope - Spindle fibers - Chromosomes - Centrioles Step 4 – Prometaphase I (skip this stage) Step 5 – Metaphase I 6. How is this stage different than metaphase of mitosis? Draw the cell as it appears during this stage. Label the following parts: - Chromosomes - Spindle fibers - Centrioles Step 6 - Anaphase I 7. How is this stage different than anaphase of mitosis? Draw the cell as it appears during this stage. Label the following parts: - Chromosomes - Spindle fibers - Centrioles Written by James Dauray http://www.docstoc.com/profile/jamesdauray Page 2 Step 7 – Telophase I 8. How is this stage different than telophase of mitosis? Draw the cell as it appears during this stage. Label the following parts: - Chromosomes - Nuclear envelope - Centrioles - Spindle Fibers Step 8 – Cytokinesis- End of Meiosis I Draw the cell as it appears during this stage. Label the following parts: - Chromosomes - Nucleolus - Centrioles - Nuclear envelope Step 9 – Interphase II 9. Does the DNA divide during this stage? 10. Are the new cells considered haploid or diploid at this stage? Explain. 11. Is each chromosome made of one or two sister chromatids at this stage? Step 10 – Prophase II 12. Does crossing-over occur during this stage? Draw the cell as it appears during this stage. Label the following parts: - Chromosomes - Centrioles - Nuclear envelope Written by James Dauray http://www.docstoc.com/profile/jamesdauray Page 3 Step 11 – Prometaphase II (Skip this stage) Step 12 – Metaphase II Draw the cell as it appears during this stage. Label the following parts: - Chromosomes - Spindle fibers - Centrioles Step 13 – Anaphase II Draw the cell as it appears during this stage. Label the following parts: - Spindle fibers - Chromatids - Centrioles Step 14 – Telophase II Draw the cell as it appears during this stage. Label the following parts: - Spindle fibers - Nuclear envelope - Chromatids - Centrioles Step 15 – Cytokinesis – End of Meiosis II 13. At the end of this stage, are the cells considered haploid or diploid? Explain. 14. At this point, are the chromosomes made of one or two sister chromatids? 15. What are the only types of cells that are produced with this type of cell division? 16. Are the daughter cells genetically identical to the parent cell? To each other? Draw the cell as it appears during this stage. Label the following parts: - Chromatids - Nuclear envelope - Centrioles Written by James Dauray http://www.docstoc.com/profile/jamesdauray Page 4
