What is the role of the urethra?

The urethra's primary role is to release urine from the body. It is a tubular structure that extends from the bladder to the external environment, allowing urine, which has been produced by the kidneys and stored in the bladder, to exit the body during the process of urination. This pathway is critical as it facilitates the excretion of waste products and excess substances from the bloodstream that have been filtered by the kidneys.

The choice addressing the storage of urine relates to the bladder's function, while the option about carrying urine to the bladder pertains to the ureters, which transport urine from the kidneys. The filtering of waste substances happens in the nephrons of the kidneys, not in the urethra itself. Therefore, emphasizing the urethra's role in expelling urine highlights its importance in the urinary system for maintaining homeostasis and eliminating waste efficiently.