The main excretory material of a frog is:

Terrestrial animals are efficient in:

Fill in the gaps:
$A$ healthy adult human excretes (on an average) ............ $gm$ of urea/day.

In humans,the waste products of nucleotide metabolism are excreted as

In the urine of a person who is not taking any food or drink,there is:

The characteristic that is shared by 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 equally in the kidneys.