In a polypeptide chain amino acids are linked togetehr by which bond?

Answer

To answer the question "In a polypeptide chain, amino acids are linked together by which bond?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Polypeptides**:
- Polypeptides are long chains made up of amino acids. They are the building blocks of proteins.

2. **Identifying Amino Acids**:
- There are 20 different amino acids that can be combined in various sequences to form polypeptides.

3. **Linking Mechanism**:
- Amino acids are linked together through a specific type of bond.

4. **Type of Bond**:
- The bond that links amino acids in a polypeptide chain is called a **peptide bond**.
- This bond is also referred to as an **amide bond**.

5. **Formation of Peptide Bond**:
- A peptide bond is formed between the alpha carboxyl group of one amino acid and the alpha amino group of the next amino acid.
- This process involves a dehydration synthesis reaction, where a molecule of water is released.

6. **Conclusion**:
- Therefore, the answer to the question is that amino acids in a polypeptide chain are linked together by a **peptide bond** (or amide bond).

### Final Answer:
Amino acids in a polypeptide chain are linked together by a **peptide bond** (or amide bond).

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