Question

Describe the role of liver, lungs and skin in excretion.

Answer 1

Role of liver in excretion : Liver is the largest gland in vertebrates. Liver changes the decomposed haemoglobin of the worn out red blood corpuscles into bile pigments bilirubin and biliverdin. It helps in detoxification of toxic chemicals and drugs. It excretes cholestrol, steroid hormones, drug metabolites and other waste materials produced in the body through bile. Urea produced in the liver (by urea cycle) is one of the major excretory product of humans.

Role of lungs in excretion : Lungs are the respiratory organs situated in the thorax. They help in filtration of air and excretion of carbon dioxide. It also helps in excretion of volatile drugs and alcohol metabolites during expiration.

Role of skin in excretion : Skin is the largest organ in the body that also helps in excretion through sweat glands and sebaceous glands. Sweat glands help in excretion of excess water, salts, uric acid and drug metabolites. Sebaceous glands secrete an oily secretion called sebum.