THE MOLECULAR BASIS OF INHERITANCE
STRUCTURE OF NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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DNA only
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RNA only
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DNA and histones
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DNA, RNA and histones
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Detailed explanation-1: -The nucleosome is the fundamental subunit of chromatin. Each nucleosome is composed of a little less than two turns of DNA wrapped around a set of eight proteins called histones, which are known as a histone octamer. Each histone octamer is composed of two copies each of the histone proteins H2A, H2B, H3, and H4.
Detailed explanation-2: -Chromosomal DNA is packaged inside microscopic nuclei with the help of histones. These are positively-charged proteins that strongly adhere to negatively-charged DNA and form complexes called nucleosomes.
Detailed explanation-3: -A single nucleosome consists of about 150 base pairs of DNA sequence wrapped around a core of histone proteins.
Detailed explanation-4: -The nucleosome core particle represents the first level of chromatin organization and is composed of two copies of each of histones H2A, H2B, H3 and H4, assembled in an octameric core with 146-147 bp of DNA tightly wrapped around it [1, 2].
Detailed explanation-5: -Chromosomes have proteins called histones that bind to DNA. DNA has two strands that twist into the shape of a spiral ladder called a helix.