BIO130H1 Chapter Notes - Chapter 4: Homologous Chromosome, Dna Replication, Telomere
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BIO130H1 Full Course Notes
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Bio130 reading 4- textbook page 473-478, 381-383, 516-518, 523-526, 531-534. Chromosomes are prepared using a staining methodology in which chromosome preparations are incubated with multicolored, fluorescent dna probes that bind specifically to particular chromosomes. By using various combinations of dna probes and computer-aided visualization techniques, each chromosome can be painted with a different virtual color, making it readily identifiable to the trained eye. If the individual chromosomes are cut out of a photograph, they can be matched up into homologous pairs (23 in humans) and ordered according to decreasing size. A preparation of this type is called a karyotype: karyotypes are routinely prepared from cultures of blood cells and used to screen. Telomeres: rather than existing as an unprotected single-stranded terminus, the overhanging strand is. Among its functions, shelterin prevents a cell"s dna repair machinery from mistaking the ends of the telomeric dna as damaged or broken dna strands, which would have serious consequences for the integrity of the genome.
