The sequence in which amino-acids are arranged in protein is called

Options

A. Primary structure
B. Secondary structure
C. Tertiary structure
D. Quaternary structure

Answer

To solve the question regarding the sequence in which amino acids are arranged in a protein, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Protein Structure**: Proteins are made up of amino acids, and their arrangement is crucial for their function. There are different levels of protein structure: primary, secondary, tertiary, and quaternary.

2. **Identifying the Primary Structure**: The primary structure of a protein refers specifically to the linear sequence of amino acids. This sequence is determined by the genetic code and is fundamental to the protein's overall structure and function.

3. **Exploring Other Structures**:
- **Secondary Structure**: This involves the local folding of the polypeptide chain into structures such as alpha helices and beta sheets, which are stabilized by hydrogen bonds.
- **Tertiary Structure**: This refers to the overall three-dimensional shape of a single polypeptide chain, formed by interactions among various side chains (R groups).
- **Quaternary Structure**: This involves the assembly of multiple polypeptide chains into a functional protein complex.

4. **Conclusion**: Given the question specifically asks for the sequence of amino acids, we can conclude that this is defined as the primary structure of the protein.

### Final Answer:
The sequence in which amino acids are arranged in a protein is called the **primary structure**.

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