Question

Which of the following is an excretory organ?

• A. Lungs
• B. Liver
• C. Skin
• D. All of the above

Answer 1

The correct option is D All of the above

In humans, kidneys are the primary excretory organs. Kidneys remove excretory waste in the form of urine (nitrogenous waste + excess salts + water).
Accessory or additional excretory organs are skin, lungs, liver and large intestine. These organs excrete the waste products in different forms such as,
i) sweat and sebum from the skin
ii) CO2 and H2O from the lungs
iii) bile from the liver involving waste products from deamination of amino acids, conversion of ammonia to urea.