Which of the following functional groups is not typically found in essential nutrients?

• A. Nitro group (${\mathrm{NO}}_2$)
• B. Carboxyl group ($-\mathrm{COOH}$)
• C. Amino group ($-\mathrm{NH}2$)
• D. Hydroxyl group ($-\mathrm{OH}$)

Answer: (A)

Verified step by step guidance

1. Identify the functional groups listed in the problem: Nitro group, Carboxyl group, Amino group, and Hydroxyl group.
2. Understand the role of each functional group in biological molecules: Carboxyl groups are found in amino acids and fatty acids, Amino groups are present in amino acids, and Hydroxyl groups are common in carbohydrates and alcohols.
3. Recognize that essential nutrients are typically composed of proteins, carbohydrates, fats, vitamins, and minerals, which commonly contain Carboxyl, Amino, and Hydroxyl groups.
4. Consider the Nitro group, which is less common in biological molecules and not typically associated with the structure of essential nutrients.
5. Conclude that the Nitro group is the functional group not typically found in essential nutrients, as it is not a common component of the major classes of biological molecules.