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Which organs belong to the excretory system?
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human body
Vintage anatomy charts of the human body showing the skeletal and muscle systems.
The human excretory system, also known as the renal system, is primarily responsible for the elimination of metabolic waste and the regulation of body fluid composition.12
The organs that constitute the renal system include:
- Kidneys: Two organs that filter the blood to remove dissolved waste products, excess salts, and water, producing urine in the process.13
- Ureters: Two thin, muscular tubes that transport urine from the kidneys to the bladder.1
- Bladder: A sac that stores urine until it is voided from the body.1
- Urethra: The tube through which urine is eliminated from the bladder to the outside of the body.1
Beyond the renal system, other organs contribute to the body's overall excretory functions:
- Lungs: These are responsible for the excretion of gaseous waste, specifically carbon dioxide, which is a byproduct of cellular metabolism.45
- Liver: This organ acts as an excretory organ by processing substances such as bilirubin, which is then excreted through the biliary ducts into the gastrointestinal tract.4
- Skin: Water and certain waste products are also lost from the body through evaporation from the skin.4