NEET 1991 · Class 12

Molecular Basis of Inheritance

71. The basic unit of nucleic acid is

  1. (A)pentose sugar
  2. (B)nucleoid
  3. (C)nucleoside
  4. (D)nucleotide

The NCERT line that answers it

Verbatim line

A nucleotide has three components – a nitrogenous base, a pentose sugar (ribose in case of RNA, and deoxyribose for DNA), and a phosphate group.

Chapter
Molecular Basis of Inheritance
Section
5.1.1 Structure of Polynucleotide Chain
Page
1
Words matched
69 of 69

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span explicitly defines a nucleotide as having three components, directly stating the basic unit of nucleic acid, which matches the correct answer.

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