Nitrogen Metabolism Dr Squier Flashcards Quizlet Overview An essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo by the organism (usually referring to humans), and therefore must be supplied in the diet Essentiality vs conditional essentiality in humans Nine amino acids are generally regarded as essential for humans isoleucine, leucine, lysine, threonine, tryptophan, methionine Essential and nonessential amino acids The amino acids that make up proteins are conventionally classified as essential or nonessential Essential or indispensable amino acids are not synthesized by the pig and must be supplied in the diet, whereas nonessential or dispensable amino acids are synthesized by the pig using nitrogen provided by Essential vs nonessential amino acids mnemonic
