Search and compare thousands of words and phrases in American Sign Language (ASL). The largest collection online.
How to sign: an amino acid that is required by animals but that they cannot synthesize; must be supplied in the diet
Categories: aminoalkanoic acid, amino acid
Within this category: arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine