Question

Urea synthesis occurs in
a. Kidney
b. Liver
c. Brain
d. Muscles

Answer 1

Hint: The end product of the protein and amino acid metabolism in the human body is called urea. The synthesis of the urea is a part of the urea cycle. This mechanism occurs either by the oxidation of amino acids or from ammonia. The French chemist Hilaire-Marin Rouelle first isolated urea from urine in 1773. Urea can be used as a fertilizer and feed supplement.

Complete answer:
The urea synthesis in mammals occurs in the liver. The first amino acid consists of nitrogen which converts into ammonia and this will be further converted into urea by the liver. Urea is less toxic for the human body as compared to ammonia.

The human body does not have the capability to store proteins and amino acids. When an excess amount of proteins is present in the human body then the excess amount of amino acids produced from the protein digestion will be transported to the liver from the small intestine. The liver will undergo various chemical reactions after the absorption of amino acids and produced urea.

The main function of the kidney in the human body is to remove waste products and excess fluid from the body. The release of urine from the body removes waste products and excess fluid.

There are various functions performed by the brain which include a person’s thoughts, memory, and speech, movement of the body, and many more. The brain is the main part of the human body that controls the whole body.

The protein filaments of actin and myosin are present in the muscle cells which produce the contraction that change the shape and length of the cells in the body.

Hence, the correct answer is option (B).

Note: We noted that the liver is the organ of the human body where urea is produced. After the production of urea in the liver, it will release into the bloodstream. The transfer of urea from the bloodstream takes place to the kidneys and in the end, it is excreted in the form of urine. Thus, urea is very less harmful to the human body as compared to ammonia.