The________ structure of a protein relates to how separate polypeptides assemble together -

Options

A. `1^(@)`
B. `2^(@)`
C. `3^(@)`
D. `4^(@)`

Answer

**Step-by-Step Solution:**

1. **Understanding Protein Structure**: Proteins are made up of long chains of amino acids, which are linked together by peptide bonds. These chains fold and interact in various ways to form different levels of protein structure.

2. **Levels of Protein Structure**:
- **Primary Structure**: This refers to the linear sequence of amino acids in a polypeptide chain. It is the most basic level of protein structure.
- **Secondary Structure**: This involves the local folding of the polypeptide chain into structures such as alpha helices and beta-pleated sheets due to hydrogen bonding.
- **Tertiary Structure**: This is the overall three-dimensional shape of a single polypeptide chain, formed by the interactions between the side chains (R groups) of the amino acids.
- **Quaternary Structure**: This level of structure refers to the assembly of multiple polypeptide chains (subunits) into a larger functional protein complex.

3. **Identifying the Correct Structure**: The question specifically asks about how separate polypeptides assemble together. This is indicative of the quaternary structure, as it involves the interaction and assembly of multiple polypeptide chains.

4. **Conclusion**: Therefore, the correct answer to the question is that the **quaternary structure** of a protein relates to how separate polypeptides assemble together.

**Final Answer**: The quaternary structure of a protein relates to how separate polypeptides assemble together.

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