Excretory System

The excretory system is a vital biological system that consists of organs and structures responsible for the removal of waste products and excess substances from the body. Its primary function is to maintain homeostasis by regulating the body's fluid balance, electrolyte balance, and internal environment, through the filtration and expulsion of metabolic waste products such as urea, uric acid, and creatinine. The system's major organs include the kidneys, ureters, bladder, and urethra. The kidneys, as central components, act as sophisticated filters, processing blood to sift out waste products and excess water, which are then transported to become urine.

Urine formed in the kidneys travels through the ureters to the urinary bladder, where it is stored until it can be excreted via the urethra during the act of urination. In addition to the renal structures, other organs like the lungs, skin, and liver also play supportive roles in excretion. The lungs expel carbon dioxide and water vapor as byproducts of respiration, the liver metabolizes various substances and produces bile containing waste for elimination, and the skin eliminates waste through sweat. All these processes and organs work together harmoniously to ensure that waste products do not accumulate to levels that can be harmful to the body.