Chapter 18-19

Last update by mayurcooled on 04/23/2014
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In eukaryotes, DNA packing seems to affect gene expression primarily by _____. (Concept 18.2)


allowing unpacked genes to be eliminated from the genome

controlling access to DNA

positioning related genes near each other

protecting DNA from mutations

enhancing the recombination of genes

Answer:
controlling access to DNA

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    causing looser packing of the chromatin at the target gene, thereby enhancing transcription

    causing tighter packing of the chromatin at the target gene, thereby enhancing transcription

    causing looser packing of the chromatin at the target gene, thereby inhibiting transcription

    causing tighter packing of the chromatin at the target gene, thereby inhibiting translation
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    In a eukaryote, activating transcription factors may stimulate gene expression by binding to a DNA site called a(n) _____. ( Concept 18.2)


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    Enhancers _____. ( Concept 18.2)


    may be located upstream or downstream from the genes they regulate

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  • smiraclelynch
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    Dioxin, produced as a by-product of various industrial chemical processes, is suspected of causing cancer and birth defects in animals and humans. It apparently acts by entering cells and binding to specific proteins, which then enter the nucleus and alter the pattern of gene expression. Therefore, dioxin acts by mimicking the action of _____. ( Concept 18.2)


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    Post-transcriptional controls _____. ( Concept 18.2)


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    Which of the following is a means of controlling eukaryotic gene expression? ( Concept 18.2)


    mRNA processing

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    What is the evolutionary significance of alternative RNA splicing? ( Concept 18.2)


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    the presence of proteasomes in the cytoplasm

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    The expression of a gene located in a tightly coiled region of DNA can be promoted by _____. ( Concept 18.2)


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