Question

What prevents the backflow of urine from the urinary bladder to the kidneys ?

Answer 1

There is a valve at the meeting point between each ureter and the bladder to prevent the backflow of urine into the kidneys. Kidney reflux means that one (or both) of these valves is not working properly. During urination, the urine travels up the affected ureter to the kidney instead of flowing out of the body.

Answer 2

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