The genetic material should be stable enough not to change with different stages of life cycle, age or with change in physiology of the organism. Stability as one of the properties of genetic material was very evident in Griffith's 'transforming principle' itself that heat, which killed the bacteria, at least did not destroy some of the properties of genetic material. This now can easily be explained in light of the DNA that the two strands being complementary if separated by heating come together, when appropriate conditions are provided. Further, 2'-OH group present at every nucleotide in RNA is a reactive group and makes RNA labile and easily degradable. RNA is also now known to be catalytic, hence reactive. Therefore, DNA chemically is less reactive and structurally more stable when compared to RNA. Therefore, among the two nucleic acids, the DNA is a better genetic material.
Which of the above statements concerning the nitrogenous bases and their properties in nucleic acids are NOT correct? S1: Purines, such as Adenine and Guanine, are double-ring structures found in both DNA and RNA. S2: Uracil is a pyrimidine nitrogenous base exclusively found in DNA, replacing Thymine. S3: In a DNA double helix, Adenine always forms two hydrogen bonds with Cytosine. S4: A nucleoside is formed when a nitrogenous base is linked to a pentose sugar through a N-glycosidic linkage. S5: The absence of a 2'-OH group in deoxyribose sugar contributes to DNA being chemically less reactive and structurally more stable than RNA.
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