| List - I | |
|---|---|
| A | Adenosine |
| B | Adenylic acid |
| C | Adenine |
| D | Alanine |
| List - II | |
|---|---|
| I | Nitrogen base |
| II | Nucleotide |
| III | Nucleoside |
| IV | Amino acid |
Choose the option with all correct matches.
Adenosine consists of adenine attached to a ribose sugar. Since it contains a nitrogen base and a sugar but no phosphate group, it is a nucleoside. Therefore, A matches with III.
Adenylic acid contains adenine, ribose sugar, and a phosphate group. A molecule containing base, sugar, and phosphate is called a nucleotide. Hence, B matches with II.
Adenine is a purine nitrogenous base found in DNA and RNA. Therefore, C matches with I.
Alanine is one of the twenty standard amino acids involved in protein synthesis. Thus, D matches with IV.
Biomolecules such as nucleotides, nucleosides, nitrogen bases, and amino acids are fundamental to molecular biology. Understanding the structural differences between them is essential for mastering genetics and biochemistry.
A nitrogenous base is an organic molecule containing nitrogen and capable of acting as a base. In nucleic acids, the bases are divided into purines and pyrimidines. Adenine and guanine are purines, while cytosine, thymine, and uracil are pyrimidines.
A nucleoside is formed when a nitrogen base attaches to a pentose sugar through a glycosidic bond. In RNA, the sugar is ribose, while in DNA, it is deoxyribose. Importantly, nucleosides do not contain phosphate groups.
A nucleotide is formed when one or more phosphate groups attach to a nucleoside. Thus, a nucleotide consists of three components: nitrogen base, sugar, and phosphate group. Nucleotides are the building blocks of nucleic acids such as DNA and RNA.
Adenylic acid, also called AMP (adenosine monophosphate), is an example of a nucleotide. It contains adenine, ribose, and one phosphate group.
Amino acids are entirely different biomolecules. They are the building blocks of proteins. Each amino acid contains an amino group, a carboxyl group, a hydrogen atom, and a variable side chain attached to a central carbon atom. Alanine is a simple non-polar amino acid.
Common mistakes include confusing nucleosides with nucleotides. Remember: no phosphate means nucleoside; presence of phosphate means nucleotide.
These concepts are frequently tested in molecular biology, DNA replication, transcription, translation, and metabolic pathways. A strong conceptual understanding ensures accuracy in matching-type questions.