Urine is carried to the urinary bladder by which structure?

The structure responsible for carrying urine to the urinary bladder is the ureters. These are muscular tubes that extend from each kidney to the bladder, functioning to transport urine generated by the kidneys to the storage site in the bladder. The ureters have a series of smooth muscle contractions, known as peristalsis, which help propel the urine downwards toward the bladder effectively.

The renal pelvis, while an important part of the urinary system, is the funnel-like structure located in the kidney that collects urine from the collecting ducts before it moves into the ureters. Nephrons are the functional units within the kidneys that filter blood and produce urine, but they do not transport urine to the bladder.

The urethra, in contrast, is the tube through which urine exits the bladder during urination, so it is not involved in transporting urine to the bladder. Thus, the correct answer highlights the specific role of the ureters in facilitating the movement of urine from the kidneys to the urinary bladder.