Tài liệu, ebook Khoa Học Tự Nhiên

Oxidative phosphorylation system in the mitochondria generates free radicals, which can damage DNA Accumulation of mtDNA mutations over time may result in age-related decline in oxidative phosphorylation Evidence in support of role of mtDNA and aging: Percentage of heart tissue with a mitochondrial deletion increases with age Brain cells of peo...

69 trang | Chia sẻ: nguyenlam99 | Ngày: 11/01/2019 | Lượt xem: 1141 | Lượt tải: 0

Incidence of abnormal phenotypes caused by aberrant chromosome organization or number is 0.004% Half of spontaneously aborted fetuses have chromosome abnormalities Incidence of abnormal phenotypes caused by single-gene mutations is 0.010%

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Specialized chromatin in central core of centromere marks this region for attachment of kinetochore proteins Central core of each centromere: Composed of unique chromatin that does not recombine and is not transcribed Surrounded by regions of heterochromatin interspersed with euchromatin Histone variant CENP-A is present in central core of all...

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All published research with SNPs uses standardized nomenclature All newly-obtained information is deposited in freely- available, public databases maintained by the NIH 29 interlinked databases at NCBI Examples dbSNP – comprehensive catalog of all human SNPs dbGap – database of results obtained in various GWASs OMIM – online compendium of ann...

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Pressing issues raised by individual genome sequences Privacy of genetic information Limitations on the use of genetic testing Patenting of DNA sequences Societal views on aging Training physicians Impact of increased longevity produced by improved medicine Somatic gene therapy vs germ-line gene therapy For further descriptions, see the var...

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Two general classes of human disorders are caused by mutations in hemoglobin genes Hemolytic anemias (e.g. sickle-cell anemia) Mutations affect amino acid sequence and the three dimensional structure of a- or b-globin chain Results in destruction of red blood cells Thallasemias Mutations result in reduction or elimination of one of the two glo...

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Mutations in genes encoding gene products for transcription, RNA processing, translation, and protein processing are often lethal Some mutations in tRNA genes can suppress mutations in protein-coding genes

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20 different amino acids R group is the side chain that is unique to each amino acid Four groups of amino acids based on R group properties (Fig 7.24b) –COOH group and –NH2 group of adjacent amino acids are joined in covalent peptide bond Polypeptides have "N terminus" and "C terminus"

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One single-strand tail invades a non-sister chromatid and forms stable heteroduplex Displacement loop (D-loop) from invaded chromatid is stabilized by single-strand binding protein Non-crossover occurs when both junctions are resolved in same plane Crossover occurs with the two junctions are resolved in different planes

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Diploid ADE2/ade2 White colonies are wildtype Red sectors are ade2/ade2 Size of sector indicates when recombination took place

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