本题目来源于试卷: Form and Function B.2 Proteins，类别为 IB生物学
[单选题]
The image shows a protein. Which level of protein struct fv 7l:ny3vjgkf inc):ep33 ao8s3rl+ure is ro79mwv h0lek 5j fs8)indicated by the le fokhm s)v 7wjel59r08tter P?
A. Primary
B. Secondary
C. Tertiary
D. Quaternary
参考答案: C
本题详细解析:
Choice C is correct because P is pointing to a disulfide bond, which can only be formed between R groups of amino acids and is a feature of the tertiary structure. The primary structure (Choice A) is the sequence of amino acids in a polypeptide chain. The secondary structure (Choice B) is the formation of alpha-helices or beta-pleated sheets through hydrogen bonding between carboxyl and amino groups of different amino acids. The quaternary structure (Choice D) exists in proteins with more than one polypeptide chain.
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