The source, an excerpt from the YouTube video "Catabolism of Amino Acids @Metabolism Made Easy," discusses the unique aspects of amino acid metabolism. It explains that amino acids are the sole nitrogen-containing molecules utilized by the body, which leads to the eventual production of ammonia during catabolism. To manage this toxic byproduct, the body employs the urea cycle to safely eliminate the nitrogen. The video also highlights that unlike glucose or fatty acids, the body lacks a storage mechanism for excess amino acids, meaning any surplus not used for synthesizing proteins or specialized products is broken down. This catabolism generates a carbon skeleton or keto acid that can then be used by the body for energy production.