MCAT Biochemistry Question 7: Answer and Explanation
Home > MCAT Test > MCAT biochemistry practice tests
Test Information
- Use your browser's back button to return to your test results.
- Do more MCAT biochemistry practice tests.
Question: 7
7. An α-helix is most likely to be held together by:
- A. disulfide bonds.
- B. hydrophobic effects.
- C. hydrogen bonds.
- D. ionic attractions between side chains.
Correct Answer: C
Explanation:
The α-helix is held together primarily by hydrogen bonds between the carboxyl groups and amino groups of amino acids. Disulfide bridges, choice (A), and hydrophobic effects, choice (B), are primarily involved in tertiary structures, not secondary. Even if they were charged, the side chains of amino acids are too far apart to participate in strong interactions in secondary structure.