Problem 20 - Objective Biology for NEET

Question

Nitrogen is one of the major constituents of (a) Protein (b) Nucleic acid (c) Vitamins and hormones (d) All of these

Step-by-Step Solution

Answer

The correct answer is (d) All of these. Nitrogen is a major constituent of proteins, nucleic acids, and vitamins and hormones.

Step 1: Analyzing the Role of Nitrogen in Protein

The nitrogen cycle is fundamental to the amino acid structure making up proteins. Amino acids are the building blocks of proteins, and nitrogen is a vital part of these compounds. So, it is clear that nitrogen is a constituent of Protein.

Step 2: Understanding the Role of Nitrogen in Nucleic Acid

Nucleic acids such as DNA and RNA contain Nitrogen bases (Adenine, Guanine, Cytosine, Thymine, and Uracil), and without nitrogen, these compounds would not exist. Therefore, Nitrogen is indeed a major component of Nucleic acids.

Step 3: Checking the Role of Nitrogen in Vitamins and Hormones

Certain vitamins (like B-vitamins) and hormones (like adrenaline) contain nitrogen in their biochemical structure. Therefore, Nitrogen is also a constituent of Vitamins and Hormones.

Step 4: Concluding the role of Nitrogen

After reviewing all the options, it is clear that nitrogen is a component of protein, nucleic acid, and vitamins and hormones, making the right answer to this question 'All of these'.

Key Concepts

Nitrogen in Proteins

Proteins are essential macromolecules in all living organisms, and nitrogen is a key element in their structure. Proteins are composed of building blocks called amino acids. Each amino acid has at least one nitrogen atom incorporated into its molecular structure.
This nitrogen is part of the amino group (-NH₂), which is essential for the formation of peptide bonds. Peptide bonds link amino acids together to form long protein chains. Therefore, without nitrogen, the fundamental structure of proteins would not be possible.
Here are some significant points about nitrogen in proteins:

• Nitrogen is essential for the formation of amino acids, which are the monomers of proteins.
• Amino acids are linked by peptide bonds, with nitrogen playing a crucial role in their formation.

Thus, the presence of nitrogen is critical for the synthesis and functionality of proteins in organisms.

Nitrogen in Nucleic Acids

Nucleic acids, such as DNA and RNA, are vital for storing and conveying genetic information in cells. Nitrogen is a crucial element in these biomolecules. Within DNA and RNA, nitrogen is found in nitrogenous bases. The major nitrogenous bases are:
Adenine (A), Guanine (G), Cytosine (C), Thymine (T), and Uracil (U). These bases pair up using hydrogen bonds to form the rungs of the DNA double helix or the backbone of RNA.
Here’s why nitrogen is indispensable in nucleic acids:

• Nitrogenous bases form the genetic code, allowing for the transmission of genetic information during cell replication and protein synthesis.
• Each base contains one or more nitrogen atoms, crucial for the stability and function of DNA and RNA.

Without nitrogen, the fundamental processes of life, such as genetic inheritance and expression, could not occur.

Nitrogen in Vitamins and Hormones

Nitrogen is also a vital component in the structures of various vitamins and hormones, which are essential for the proper functioning of biochemical processes in living organisms. Many vitamins, like the B-complex vitamins, and hormones such as adrenaline, incorporate nitrogen in their molecular structures.
Here's how nitrogen functions in vitamins and hormones:

• Nitrogen provides unique chemical properties that enable these molecules to interact effectively with biological pathways.
• In hormones like adrenaline, nitrogen atoms allow the molecule to bind to receptors, triggering specific responses.
• For vitamins, nitrogen often participates in enzymatic reactions, which are crucial for metabolism and energy production.

Therefore, the importance of nitrogen in vitamins and hormones underscores its role in maintaining health and homeostasis in organisms.