20 amino acids: alanine arginine asparagine aspartic acid cysteine glutamine glutamic acid glycine histidine isoleucine etc

acid acids alanine amine amino arginine asparagine aspartic background biology carbon carboxyl chemical chemistry cysteine element formula glutamic glutamine glycine health histidine icon isoleucine laboratory leucine lysine medicine methionine molecular molecule organic periodic phenylalanine proline research school science serine sign structure symbol test threonine tryptophan tube tyrosine valine vector white