Excretory system concern with the elimination of harmful and waste products formed in the body. The main excretory organs are lungs, kidneys, skin, and large intestine. Lungs give off carbon dioxide and water vapor, thus, it is an organ of respiration as well as excretion. Skin secretes sweat. Large intestine excretes waste matter of digestion, as feces while kidneys excrete urine.
Functions of the kidney. The main function of the kidney is to take away the nitrogenous waste products of the body. kidneys also re-absorb certain useful constituents such as glucose, water, and salts.
Functions of skin. Skin protects the body , regulates the temperature of the body, excretes the waste products ,gives the sense of touch and stores reserve food.
