BIOLOGY
STRUCTURE OF NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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supercoiling of chromosomes
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regulation of transcription
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both of these
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neither of these
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Detailed explanation-1: -The nucleosome thus serves not only as a general gene repressor, but also as a repressor of all transcription (genic, intragenic, and intergenic). The core nucleosome performs a fundamental regulatory role, apart from the histone “tails, ” which modulate gene activity.
Detailed explanation-2: -Each nucleosome is composed of DNA wound 1.65 times around eight histone proteins.
Detailed explanation-3: -Nucleosomes are the basic packing unit of DNA built from histone proteins around which DNA is coiled. They serve as a scaffold for formation of higher order chromatin structure as well as for a layer of regulatory control of gene expression.
Detailed explanation-4: -During transcription elongation nucleosomes are acetylated and transferred behind RNA polymerase II where they are required to suppress spurious transcription initiation within the body of the gene.