Essential Amino Acids (For Humans) Differ from Nonessential Amino Acids

Multiple Choice

Essential amino acids (for humans) differ from nonessential amino acids in that

A) nonessential amino acids are synthesized in simple reaction pathways compared to complex pathways for most essential amino acids.
B) essential amino acids are generally synthesized directly from citric acid cycle intermediates, but not nonessential amino acids.
C) microorganisms and animals cannot synthesize essential amino acids but plants can.
D) animals cannot synthesize essential amino acids because they have lost the ability to carry out transamination reactions.
E) All of the answers are correct.