Which structure is responsible for urine storage in the body?

The bladder is the structure responsible for urine storage in the body. It is a muscular sac located in the pelvis that can expand and contract as it fills and empties. As urine produced by the kidneys flows through the ureters, it collects in the bladder until a certain volume triggers the urge to urinate. This design allows for efficient storage of urine, which can be released in a controlled manner.

The kidneys, while essential for the production of urine through filtration of blood, do not store urine. The ureters are tubes that transport urine from the kidneys to the bladder but do not serve as storage. The urethra is the passage through which urine is expelled from the bladder to the outside of the body, rather than a storage site. This highlights the unique function of the bladder in the urinary system, distinguishing it from other structures involved in urine production and elimination.