BSC 2010 Lecture Notes - Lecture 5: Punnett Square, Black Body, Human Genome
25 Mar 2015
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Bsc2010:integrative principles of biology- lecture #5: chromosome and linkage. Human genome: 23 chromosome types and 2400 genes; 1050 genes per chromosome. Recessive parent in tc gee rates only one type of gamete. When genes are liked they are physically tied to the same chromosomes and that causes loss of variation. Fruit flies: vestigial wings recessive, black body color recessive. Wild type: this is the most common you see, anything deviating from that will be mutant. Ratio of genes located on same vs different chromosomes. 1:1:1:1 vs 1:1:0:0 results: 965:944:206:185 ( due to crossover where chromosome exchanges physical pieces in prophase 1 of meiosis) Crossing over restores genetic variation lost by linkage. Linkage allows for the coordinated movements of genes during mitosis and meiosis ( that"s its advantage over crossing over >>>> clicker question. Cis and trans heterozygote: you need to know where they are located on the chromosome. Genetic gene map: use of recombination frequency from tc to map genes.
