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Unformatted text preview: I. At telophase I (Figure 3.12) the chromosomes reach the opposite poles of the cell and begin to decondense. The nuclear membrane then reforms around the chromosomes. Following telophase I, cytokinesis occurs (Figure 3.12), then the cell proceeds directly to meiosis II.
What are the chances that two people will have a second child who is genetically identical to their ﬁ rst child? Random fertilization – a zygote represents the combination of parental probabilities. In humans there are 8 million (223) possible combinations of parental chromosomes in sex cells; so, there are 64 trillion possible combinations 6 in zygotes (8 million x 8 million) The genetic variation that results from independent assortment and random fertilization plus the variation that results from crossing over makes the number of genetic possibilities for any particular zygote astronomical The sequence of events for meiosis II is identical to that of mitosis, except that two cells are now dividing (Figure 3.12). Cytokinesis follows mei...
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