Which statement is true about the peptide bond in proteins?

Question

BlackTom AI · Accepted Answer

Restating the question: Which statement is true about the peptide bond in proteins?

Option a: It is freely rotating due to side-chain flexibility.
- This is incorrect. The peptide bond has partial double-bond character due to resonance between the carbonyl oxygen and the amide nitrogen, which restricts rotation about the C–N bond. Side-chain flexibility does not make the peptide bond freely rotatable.

Option b: It has a tetrahedral geometry due to sp³ hybridization.
- This is false. The peptide bond carbonyl carbon and the amide nitrogen adopt a planar arrangement (roughly sp² hybridization on those centers), not a tetrahedral geometry. The resonance gives rise to planarity of the amide bond.

Option c: It is planar and exhibits partial double-bond character.
- This is true. The peptide bond is planar because of resonance between the carbonyl and the amide nitrogen, which gives it partial double-bond character and restricts rotation, resulting in a flat configuration.

Option d: It forms only between charged amino acids.
- This is incorrect. Peptide bonds form between any amino acids, linking the carboxyl terminus of one amino acid to the amino terminus of the next, regardless of side-chain charge. Charge has nothing to do with the formation of the backbone bond.

Option e: It rotates around the omega angle to allow folding.
- This is misleading. While the backbone does have an omega angle, rotation about the peptide bond itself is largely restricted due to the partial double-bond character; the typical trans peptide bond fixes the geometry and does not freely rotate to facilitate folding. Therefore this statement overstates the ease of rotation and is not accurate as a general truth about peptide bonds.

In summary, each incorrect option misstates fundamental aspects of peptide bond structure or dynamics, while option c correctly captures the essential planarity and partial double-bond character that define the peptide bond.

Which statement is true about the peptide bond in proteins?单项选择题

类似问题

Which of the following defines a peptide bond?

What bond is forming between the amino acids?

In which security measure will you find anti-virus software?

What are user permissions?

Which security measure will stop someone reading your messages if they find your smart phone?

On a network a firewall

What is the name for emails that are sent to users, pretending to be from their bank and asking for username and password?

To stop users of a network from playing games all day instead of working, which would be the best security measure to use?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单