BIOLOGY
CARBOHYDRATES
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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adenine and guanine
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cytosine and uracil
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purines and pyrimidines
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cytosine and thymine
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Detailed explanation-1: -Nitrogenous bases present in the DNA can be grouped into two categories: purines (Adenine (A) and Guanine (G)), and pyrimidine (Cytosine (C) and Thymine (T)). These nitrogenous bases are attached to C1’ of deoxyribose through a glycosidic bond. Deoxyribose attached to a nitrogenous base is called a nucleoside.
Detailed explanation-2: -DNA base pair. Under normal circumstances, the nitrogen-containing bases adenine (A) and thymine (T) pair together, and cytosine (C) and guanine (G) pair together. The binding of these base pairs forms the structure of DNA .
Detailed explanation-3: -The purines in DNA are adenine and guanine, the same as in RNA. The pyrimidines in DNA are cytosine and thymine; in RNA, they are cytosine and uracil.
Detailed explanation-4: -Nitrogen Bases There are two kinds of nitrogen-containing bases-purines and pyrimidines. Purines consist of a six-membered and a five-membered nitrogen-containing ring, fused together. Pyridmidines have only a six-membered nitrogen-containing ring. There are 4 purines and 4 pyrimidines that are of concern to us.
Detailed explanation-5: -They are nitrogenous bases that make up the two different nucleotides in DNA and RNA. Purines (adenine and guanine) are two-carbon nitrogen ring bases while pyrimidines (cytosine and thymine) are one-carbon nitrogen ring bases.