Topics: Amino acid digestion, Amino acid absorption, Deamination, Oxidative deamination, Transdeamination, Decarboxylation, urea cycle, Phenylketonuria, Alkaptonuria, Maple syrup urine disease, Homocystinuria, Creatine degradation, Urinary creatinine, Purine, Pyrimidine Metabolism, Nucleosides, Nucleotides, Chromosomes, Messenger RNA, Transfer RNA, Ribosomal RNA, Folic Acid, Anaemia, Nutritional anaemia, Microcytic anaemia