Amino acids are the building blocks of

Options

A. Carbohydrates
B. Vitamins
C. Fats
D. Proteins

Explanation

**Step-by-Step Solution:**

1. **Understanding Amino Acids:**
- Amino acids are organic compounds that serve as the fundamental building blocks of proteins. Each amino acid contains a central carbon atom, an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom, and a variable side chain (R group) that determines the specific characteristics of each amino acid.

2. **Formation of Proteins:**
- When amino acids link together through peptide bonds, they form proteins. This process is known as protein synthesis. The sequence and number of amino acids in a protein determine its structure and function.

3. **Types of Proteins:**
- Proteins can be classified into different structural levels:
- **Primary Structure:** The linear sequence of amino acids.
- **Secondary Structure:** The folding or coiling of the amino acid chain into structures such as alpha-helices and beta-pleated sheets.
- **Tertiary Structure:** The three-dimensional shape formed by the overall folding of the polypeptide chain.
- **Quaternary Structure:** The arrangement of multiple polypeptide chains into a single functional protein.

4. **Classification of Amino Acids:**
- Amino acids are categorized into two main types:
- **Essential Amino Acids:** These cannot be synthesized by the body and must be obtained from the diet (e.g., valine, leucine, tryptophan).
- **Non-Essential Amino Acids:** These can be synthesized by the body and do not need to be obtained from the diet (e.g., alanine, aspartic acid).

5. **Conclusion:**
- Therefore, the answer to the question "Amino acids are the building blocks of" is **proteins**.

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