The Three-Dimensional Structure of Macromolecules Is Formed and Maintained Primarily

question 83

Multiple Choice

The three-dimensional structure of macromolecules is formed and maintained primarily through noncovalent interactions. Which one of the following is NOT considered a noncovalent interaction?

• A) carbon-carbon bonds
• B) hydrogen bonds
• C) hydrophobic interactions
• D) ionic interactions
• E) van der Waals interactions

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Definitions:

Hydrogen Bonding

Hydrogen bonding is a type of weak chemical bond that occurs when a hydrogen atom that is covalently bonded to a highly electronegative atom, such as oxygen or nitrogen, experiences attraction to another electronegative atom.

Secondary Structure

The secondary structure of proteins involves the local folding or coiling of the peptide chain into structures such as alpha-helices and beta-sheets, primarily stabilized by hydrogen bonds.

Alpha-Helical

Pertaining to the alpha-helix structure, a type of secondary structure of proteins, characterized by a right-handed coil.

Beta-Pleated Sheet

A type of secondary structure found in proteins wherein the backbone is extended into a zigzag shape and strands are connected by hydrogen bonds.