When a nucleotide from DNA containing adenine is hydrolyzed, the products obtained are
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Adenine, deoxyribose sugar and phosphoric acid.
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To understand why, we can look at the chemical composition of a DNA nucleotide. A nucleotide is the basic building block of nucleic acids and consists of three distinct chemical components. When it undergoes complete hydrolysis (the chemical breakdown of a compound due to reaction with water), it breaks back down into these three starting units.
Components of a DNA Nucleotide
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Nitrogenous Base: In this specific case, the base is Adenine.
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Pentose Sugar: Because the source is DNA (Deoxyribonucleic Acid), the sugar is always $\beta$-D-2-deoxyribose. (If it were RNA, the sugar would be ribose).
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Phosphate Group: This is derived from phosphoric acid ($H_3PO_4$) and links the nucleotides together in a chain.
Distinguishing Key Terms
It is helpful to distinguish between a nucleotide and a nucleoside, as they result in different products upon hydrolysis:
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Nucleotide Hydrolysis: Yields Base + Sugar + Phosphoric acid.
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Nucleoside Hydrolysis: Yields only Base + Sugar (a nucleoside lacks the phosphate group).
Why the other options are incorrect:
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Adenine, ribose sugar and phosphoric acid: This describes a nucleotide from RNA, not DNA.
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Adenine and ribose sugar only: This describes an RNA nucleoside.
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Adenine and deoxyribose sugar only: This describes a DNA nucleoside.
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