Proteins are chemically different from carbohydrates and fats because they also contain:a.Nitrogen.b.Phosphorus.c.Sodium.d.Iron.

Break Down the Problem

1. Identify the key distinguishing feature of proteins compared to carbohydrates and fats.
2. Determine which element among the options is unique to proteins.

Relevant Concepts

• Proteins, carbohydrates, and fats are all macromolecules but have different compositions.
• Proteins are made of amino acids, which contain carbon, hydrogen, oxygen, and nitrogen.
• Carbohydrates and fats typically do not contain nitrogen.

Analysis and Detail

1. Nitrogen: Proteins contain nitrogen as part of their amino acid structure.
2. Phosphorus: Typically found in nucleic acids (DNA, RNA) and energy molecules (ATP), not a primary component of proteins.
3. Sodium: An essential mineral that helps with various bodily functions, but not a structural component of proteins.
4. Iron: Important for numerous biological functions (like hemoglobin), but again not a fundamental component of proteins.

Verify and Summarize

• The primary element that uniquely distinguishes proteins from carbohydrates and fats is nitrogen.

Final Answer

a. Nitrogen.