Final answer:
The major organic waste product found in human urine is urea, which is produced from the nitrogen found in amino acids and serves as a non-toxic way to excrete toxic ammonia from the body.
Step-by-step explanation:
The major organic waste product found in urine samples is urea. Urea is generated from two ammonia molecules and a carbon dioxide molecule, making it the principal waste product in mammals. It is produced from nitrogen that originates from amino acids and is excreted through the urine. While there are other nitrogenous waste products such as creatinine, ammonia, and uric acid that can be found in urine, urea is the most significant one as it is a non-toxic molecule formed from toxic ammonia and carbon dioxide. This conversion is crucial as ammonia itself is extremely toxic, so it must be rapidly converted into urea in the liver for safe excretion.