Variable expression of the MERRF syndrome arises from O recombination between nuclear and mtDNA O homoplasmic cells O mitotic segregation O nuclear genes O environmental factors

. Among adults with Turner syndrome, it has beenfound that a very high proportion are genetic mosaics.These are of two types: In some individuals, themajority of cells are XO, but a minority of cellsare XX. In other Turner individuals, the majorityof cells are XO, but a minority of cells are XY.Explain how these two patterns of somatic mosaicscould arise.

of my celle chose are wels smaller than normal. According to Model 1, what part(e) of the cell cycle is (ere) ou likely being affected? Some cancerus me 7. In Model 1, if the length of the arrow represents time, then for those cancerous cells, what hap pens to the time that is necessary for the cell cycle? What implication might this have for doctors who are treating cancer patients? Why? Living things must grow and develop. At times they suffer injuries or damage, or cells simply wear out. New cells must be formed for the organism to survive. What process must occur to make a new, properly- functioning cell? Model 1 - Mitosis as Part of the Cell Cycle Prophase Metaphase Anaphase Mitosis How do living things grow and repair themselves! Replicated chromosome (2 sister chromatids) 0000 * Centriole Spindle fibers Nuclear membrane Telophase 1. Refer to Model 1. List the four phases in the mitosis process. 2. Where is mitosis in the cell cycle? Before 3. What three phases of the cell cycle…

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Describe the similarities and differences between homologousrecombination involving sister chromatid exchange (SCE) and thatinvolving homologs. Would you expect the same types of proteinsto be involved in both processes? Explain.

A cell with a prominent nucleolus is most likely O Completing apoptosis Performing crossing over events O Producing ribosomes for protein synthesis O Undergoing meiosis I