Essential Amino Acids Arginine (Arg) Tryptophan (Trp) -Threonine(Thr) Methionine (Met) Lysine (Lys) ■Histidine(His) Valine (Val) ·Leucine(Leu) -Phenylalanine(Phe)Isoleucine(lle) Chapter 24 7Chapter 24 7 Essential Amino Acids ▪ Arginine (Arg) ▪ Threonine (Thr) ▪ Lysine (Lys) ▪ Valine (Val) ▪ Phenylalanine (Phe) ▪ Tryptophan (Trp) ▪ Methionine (Met) ▪ Histidine (His) ▪ Leucine (Leu) ▪ Isoleucine (Ile)