Question

Deamination is the first step in urea formation. It means the
(A) Reduction of ammonia
(B) Oxidation of ammonia
(C) Addition of amino group to a non- amino organic molecule
(D) Removal of amino group from an amino acid

Answer 1

Hint: Deamination is defined as the removal of the amino acid group from the molecules of the protein. The enzyme that helps in the process of deamination is called deaminase. This process mainly occurs when there is the excess protein intake. It takes place in the liver and the kidney.

Complete answer:
The amino acid group that is separated from the protein is removed into the blood. This chemical part of the excretion first takes place at the liver. The liver separates excess amino groups from the protein to the ammonia. This ammonia is converted into the urea by the addition of the carbon dioxide. Which in turn is excreted by the kidney as the urine. The protein that remains unseparated is separated into the carbon and hydrogen and it is recycled for the process of the production of the energy by the cells. So, the correct answer is that deamination is the first step in urea formation. It means the removal of an amino group from an amino acid.

Hence the correct answer is option(D)

Note: After the step of deamination, the urea cycle takes place. This urea cycle is also known as ornithine cycle. It is the biochemical process that converts the ammonia into the urea or the uric acid. This process takes place in the kidney.