At some points a protein molecule may be folded back on itself. This called _____ structure and folds or coils are held together in place by _______.

Options

A. `2^(@)`, H-bonds
B. `2^(@)`, peptide bonds
C. `3^(@)`, H-bonds
D. `1^(@)`, peptide bonds

Answer

To answer the question, we need to identify the type of structure formed when a protein molecule folds back on itself and the type of bonds that hold this structure together.

1. **Identify the structure formed when a protein folds back on itself**:
- When a protein molecule folds back on itself, it forms a **secondary structure**. This structure is characterized by specific patterns such as alpha helices and beta sheets.

2. **Determine the type of bonds that hold the secondary structure together**:
- The folds or coils in the secondary structure are primarily held together by **hydrogen bonds**. These bonds form between the hydrogen atom of one amino acid and the oxygen atom of another, stabilizing the structure.

**Final Answer**:
At some points, a protein molecule may be folded back on itself. This is called **secondary structure**, and folds or coils are held together in place by **hydrogen bonds**.

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