Which of the following is true of protein structure? A. Tertiary protein structure emerges when there is more than one peptide chain in a protein. B. Peptide bonds join the amine group on one amino acid with the R group of another amino acid. C. Secondary protein structures involve hydrogen bonding between amine and carboxyl groups. D. Peptide bonds are formed by hydrolysis.

Answer: C. Secondary protein structures involve hydrogen bonding between amine and carboxyl groups.

Explanation: Proteins are linear polymers made up of amino acids. They are large marcomolecules in living cells that are essential for cell and body growth.

We have four types of protein structures:

Primary Structure: This is formed when amino acids are linked by peptide bonds to form polypeptide chains.

Secondary Structure: This structure is formed when polypeptide chains fold into 3D stuctures such as the alpha helix and beta pleated sheet.

Tertiary Structure: This structure is formed when proteins soluble in water fold Into compact structures with nonpolar centers.

Quaternary Structure: This structure is formed when multiple polypeptide chains form a protein. Each polypeptide chain is referred to as a subunit.