GENERAL HISTOLOGY

Detailed explanation-1: -Reptiles, birds, land snails and insects excrete nitrogenous wastes as uric acid in the form of pellet or paste with a minimum loss of water and are called as uricotelic animals. These animals can excrete uric acid as solid crystals to conserve water.

Detailed explanation-2: -Key Points. Nitrogenous wastes in the body tend to form toxic ammonia, which must be excreted. Mammals such as humans excrete urea, while birds, reptiles, and some terrestrial invertebrates produce uric acid as waste.

Detailed explanation-3: -Birds excrete nitrogenous wastes as uric acid in the form of pellet or paste with minimum loss of water and are called uricotelic animals.

Detailed explanation-4: -Birds produce uric acid – which is white and insoluble, rather than the soluble urea we excrete – as a water-saving measure to keep body weight lower. The faecal matter is the dark part of the dropping.

Detailed explanation-5: -Birds excrete uric acid, which does not dissolve easily in water, is relatively nontoxic, and can be voided nearly dry. Birds, however, must use much more energy to produce the uric acid than mammals do to produce urea. Thus they pay a price for their efficient water retention.