Which Group Consists Only of Amino Acids with Polar Side

Question

Which group consists only of amino acids with polar side chains?
A) serine, threonine, and leucine
B) serine, threonine, and cysteine
C) serine, threonine, and valine
D) serine, threonine, and isoleucine

Accepted Answer

Serine and threonine both have polar side chains due to the presence of hydroxyl groups. Cysteine also has a polar side chain due to the presence of a sulfhydryl group. Leucine, valine, and isoleucine all have non-polar side chains.