Primary structure of protein is based upon the

Options

A. hydrogen bonding
B. van der Waals, forces
C. Ionic bonding
D. covalent bonding

Answer

**Step-by-Step Solution:**

1. **Understanding Proteins and Peptides**:
- Proteins are large biomolecules made up of smaller units called amino acids. When two amino acids bond together, they form a peptide.

2. **Formation of Peptides**:
- Peptides are formed through a process called condensation reaction, where a molecule of water is removed as two amino acids combine. This involves the carboxyl group of one amino acid and the amino group of another.

3. **Example of Amino Acids**:
- For instance, consider glycine (with a carboxyl group and an amino group) and alanine (which has a methyl side chain). When these two amino acids react, they form a peptide bond.

4. **Peptide Bond Formation**:
- The bond that forms between the amino group of one amino acid and the carboxyl group of another is known as a peptide bond or amide linkage. This bond is a type of covalent bond.

5. **Primary Structure of Proteins**:
- The primary structure of a protein refers to the specific sequence of amino acids linked together by peptide bonds. This structure is determined solely by covalent bonding.

6. **Conclusion**:
- Therefore, the primary structure of protein is based upon covalent bonding, specifically the peptide bonds formed between amino acids.

**Final Answer**: The primary structure of protein is based upon covalent bonding (peptide bonds).

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