NCERT Solutions for Class 11 Biology Chapter 19 Excretory Products and Their Elimination


The chapter covers topics such as Human Excretory System, Urine Formation, Function of the Tubules, Mechanism of Concentration of the Filtrate, Regulation of Kidney Function, Micturition, Role of other Organs in Excretion, Disorders of the Excretory System and more. Elimination of metabolic waste products from the animal body to regulate the composition of body fluids and tissues is called excretion. These waste products include ammonia, uric acid, urea, carbon dioxide and ions.

Ammonia is the most toxic and uric acid is the least toxic. The process of removing ammonia is called ammonotelism and organisms that excrete ammonia are called ammonotelic (bony fishes, aquatic amphibians and insects). The organism that release urea as nitrogenous wastes are called ureotelic (mammals, terrestrial amphibians). The organism that excretes uric acids is called uricotelic