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Cell Division. IB Biology. Unravelling a chromosome:. Access excellence. Human Life Cycle. Diploid Zygote 46. Haploid Sperm 23. Adult 46. Haploid Egg 23. fertilisation. Can you draw and label a pie chart for the above data?. Mitosis in Action.
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Cell Division IB Biology
Unravelling a chromosome: Access excellence
Human Life Cycle Diploid Zygote 46 Haploid Sperm 23 Adult 46 Haploid Egg 23 fertilisation
Mitosis in Action http://www.johnkyrk.com/mitosis.html http://www.sumanasinc.com/webcontent/animations/content/mitosis.html
Stages of Mitosis 1. Interphase: Just before a cell divides by mitosis the chromatin condenses into chromosomes. The chromosomes replicate themselves. The original chromosome and its replicate are called chromatids and they are held together by acentromere. chromosome chromatid centromere
2. 3. Prophase: Chromatids become visible as they shorten and thicken. The nuclear membrane disappears and spindle fibres are produced. Metaphase: The chromatids arrange across the middle of the cell (equator). Their centromeres are attached to spindle fibres which are attached to centrioles at each pole.
5. 4. Anaphase: The spindle fibres shorten and pull the chromatids apart to opposite ends of the cell. One set goes to one pole, the other to the other one. Telophase: The nuclear membranes form. The identical sets of chromosomes form groups at either end of the cell and start to uncoil. The cytoplasm divides and forms two identical (daughter) cells with the same number of chromosomes.
Summary http://www.youtube.com/watch?v=7hQ5xXJSmK4 http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/