Question

The characteristic(s) common to urea, uric acid and ammonia is/are:

(i) They are nitrogenous wastes.
(ii) They all need very large amount of water for excretion.
(iii) They are all equally toxic.
(iv) They are produced in the kidneys.

• A. (i), (iii) and (iv)
• B. (i) only
• C. (i) and (iii)
• D. (i) and (iv)

Answer 1

The correct option is B (i) only

Ammonia, urea and uric acid are the major forms of nitrogenous wastes excreted by the animals. They are produced in the liver.
Ammonia is the most toxic form and requires large amount of water for its elimination, whereas uric acid, being the least toxic, can be removed with a minimum loss of water.