OBJECTIVE LIFE SCIENCE
MOLECULAR BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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amino acids.
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sugars and phosphates.
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complementary bases.
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adenine and uracil.
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Detailed explanation-1: -Two polynucleotide chains of DNA are wound around the same axis and are held together by complementary base pairing between nitrogenous bases of two strands in the same plane. Adenine of one strand forms two hydrogen bonds with thymine of other strand and guanine forms three hydrogen bonds with cytosine.
Detailed explanation-2: -Double-stranded DNA consists of two polynucleotides that are arranged such that the nitrogenous bases within one polynucleotide are attached to the nitrogenous bases within another polynucleotide by way of special chemical bonds called hydrogen bonds.
Detailed explanation-3: -Hydrogen bonds are present in between complementary bases. This complementary base pairing holds the two antiparallel strands of DNA together. There are 3 hydrogen bonds between G and C while 2 are present in between A and T.