Question

The products of proteins catabolism are

• A. NH${}_3$,CO${}_2$ and Urea
• B. Urea, CO${}_2$ and NH
• C. Urea, NH${}_3$ and uric acid
• D. Urea, NH${}_3$, alanine and creatine

Answer 1

The correct option is A NH${}_3$,CO${}_2$ and Urea

Proteins are nitrogen containing biomolecules. They are catabolised into carbon dioxide, ammonia, urea in terrestrial vertebrates. Aquatic animals directly excrete ammonia as ammonia is very toxic and highly soluble in water. Terrestrial vertebrates do not excrete ammonia as they have to conserve water and excreting ammonia will require a lot of water. Thus terrestrial vertebrates like mammals convert ammonia into urea in liver and excrete urea. Uric acid is least soluble in water and is excreted by birds.