Quiz 2 and Test 2 Review - BHCM4116 Smr II 2025

Which of the following is NOT a function of proteins?

• Energy storage

• Enzyme catalysis

• Structural support

• Signal transduction

Which amino acid is achiral?

• Alanine

• Glycine

• Leucine

•   Serine

Answer explanation

Chirality means that there are four different molecules bound to the central alpha carbon, and glycine has a hydrogen for a side chain, meaning the alpha carbon has two hydrogens bound, making it achiral - also meaning it has no stereochemistry

At physiological pH (~7.4), which group of amino acids is typically positively charged?
  

• Hydrophobic

•   Polar

• Acidic

•    Basic

Which of the following amino acids can form disulfide bonds?

• Serine

• Cysteine

• Threonine

• Tyrosine

The pKa of the carboxyl group of an amino acid is approximately:

• 2

• 5

• 7

• 9

Which level of protein structure is defined by the sequence of amino acids?

• Primary 

• Secondary

• Tertiary

•    Quaternary

Which of the following amino acids is a helix breaker?

• Alanine

• Leucine

• Proline

• Glutamate

Which protein structure level involves interactions between multiple polypeptide chains?

• Primary 

• Secondary

• Tertiary

• Quaternary

Which of the following is true about peptide bonds? 

• They are formed by hydrolysis

• They allow free rotation

• They are planar and rigid

• They are ionic in nature

Which of the following is NOT a noncovalent interaction stabilizing tertiary structure? 

• Hydrogen bonds

• Ionic interactions

• Disulfide bonds

• Hydrophobic interactions