Chapter 1, Problem 1.37P

Interpretation Introduction

(a)

Interpretation:

For each nucleotide, the phosphate group, the sugar group, and the nitrogenous base are to be circled and labeled.

Concept introduction:

The small molecular units from which nucleic acids are made of are known as nucleotides. Every nucleotide has three components: a phosphate group, a cyclic sugar, and a nitrogenous base. Thus, adjacent nucleotides are connected by a bond between the sugar group of one nucleotide and the phosphate group of another.

Interpretation Introduction

(b)

Interpretation:

For each nucleotide, it is to be stated whether it can be part of RNA or DNA.

Concept introduction:

In both RNA and DNA, the backbone of a single strand consists of alternating sugar and phosphate group. In RNA, the sugar group is ribose whereas in DNA, it is deoxyribose. In the ribose sugar, the $2\text{'}$ carbon atom has one hydrogen and one hydroxyl group attached. While in deoxyribose, the $2\text{'}$ carbon atom has two hydrogen atoms attached. Thus, as the name suggests, deoxyribose has one less oxygen atom than ribose, at the $2\text{'}$ carbon.

Interpretation Introduction

(c)

Interpretation:

The nitrogenous base in each of the given nucleotides is to be identified.

Concept introduction:

Nucleotides are distinguished from one another by identifying the nitrogenous bases attached to the sugar group. In both RNA and DNA, it is the specific sequence of the nitrogenous bases that determines the genetic information that is stored or carried. There are four types of five nitrogenous bases that could be present in RNA and DNA. Uracil, guanine, adenine, cytosine, thymine are the nitrogenous bases present in RNA and DNA. In a nucleotide, the $1\text{'}$ carbon atom of the sugar group becomes directly bonded to nitrogen atom in the above nitrogenous bases.