Question

Accessory excretory human organ is

• A. skin
• B. skin and liver
• C. skin and lungs
• D. All of these

Answer 1

The correct option is D All of these

In addition to the urinary system, the skin, lungs and liver of vertebrates are accessory excretory organs. Human skin possesses glands for secreting two fluids on its surface, namely sweat from the sweat glands and sebum from sebaceous glands. The lungs give out carbon dioxide. Deamination of amino acids results in the production of ammonia (NH₃). Ammonia is an extremely toxic base and its accumulation in the body would quickly be fatal. However, the liver contains a system of carrier molecules and enzymes which quickly converts the ammonia (and carbon dioxide) into urea.