A variable group is attached on `alpha`-carbon in amino acid called____

Answer

To answer the question, "A variable group is attached on α-carbon in amino acid called____", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Structure of Amino Acids**:
- Amino acids have a general structure that includes an α-carbon (alpha carbon), an amino group (-NH2), a carboxylic group (-COOH), a hydrogen atom, and a variable side chain.

2. **Identifying the Variable Group**:
- The variable group in an amino acid is represented by the letter "R". This "R" group is what differentiates one amino acid from another.

3. **Significance of the Variable Group**:
- The "R" group can vary in size, shape, and composition, which leads to the diversity of amino acids. Each amino acid has a unique "R" group, which determines its properties and functions.

4. **Conclusion**:
- Therefore, the variable group attached to the α-carbon in an amino acid is called the "R group".

### Final Answer:
The variable group is attached on α-carbon in amino acid called **R group**.

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