MCQ Detailed View

Urine is a liquid waste product that is produced in the kidneys, which are vital organs of the human excretory system. The main function of the kidneys is to filter the blood, removing waste materials, excess salts, and extra water, which are then excreted as urine. This process is crucial for maintaining the body’s fluid balance, removing harmful substances, and keeping the internal environment stable.

Blood reaches the kidneys through the renal arteries. Inside each kidney are millions of tiny filtering units called nephrons. These nephrons remove unwanted substances such as urea (a nitrogen-based waste product formed from protein metabolism), creatinine, and excess ions from the blood. The cleaned blood returns to circulation, while the waste material is combined with water to form urine.

After being produced in the kidneys, urine travels through thin tubes called ureters to the urinary bladder, where it is temporarily stored. When the bladder is full, the urine is excreted from the body through the urethra.

Other organs listed in the options do not produce urine:

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  Lungs are responsible for gas exchange (oxygen intake and carbon dioxide removal).

  
  


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  Large intestine absorbs water and forms solid feces but does not produce urine.

  
  


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  Liver helps in detoxifying chemicals, producing bile, and breaking down harmful substances but does not make urine.

  
  

The process of urine formation is essential for removing toxic substances and maintaining electrolyte balance in the body. Without properly functioning kidneys, waste products would accumulate in the blood, leading to serious health problems.Therefore, the correct answer is Kidneys, as they are the primary organs where urine is produced before being excreted from the body.