Final answer:
Ureteroscopic stone removal is a true alternative for large kidney stones or when ESWL is inadvisable. A kidney stone causing blockage is typically located in the ureter. Urine flow is not solely gravity-driven, and transitional epithelium lines the bladder.
Step-by-step explanation:
Ureteroscopic stone removal is indeed an alternative to extracorporeal shock wave lithotripsy (ESWL) when kidney stones are too large or ESWL is not recommended. This statement is true. Ureteroscopy involves the use of a small camera, called a ureteroscope, that is passed through the bladder and into the ureter to locate and remove the stone. For particularly large stones, additional methods such as laser lithotripsy can be used in conjunction with ureteroscopy to break the stone into smaller, passable pieces.
A kidney stone causing a blockage in the urinary tract is likely located in the ureter, the tube connecting the kidney to the bladder. The blockage can cause severe pain, known as renal colic, and may require intervention.
In terms of urinary system structures, the urethra is the tube that carries urine from the bladder out of the body, the nephron is the functional filtration unit within the kidneys, the ureters are the tubes that carry urine from the kidneys to the urinary bladder, and the urinary bladder is the organ that collects and stores urine until it is expelled from the body.
The male urethra is longer and divided into multiple segments, whereas the female urethra is shorter and has only one segment. Additionally, the male urethra plays a role in both the urinary and reproductive systems, while the female urethra serves solely for urination.
Urine does not travel through the urinary system due solely to gravity; muscle contractions and pressure differences also play a role. This statement is false. Urination refers to the elimination of urine from the body, which is correct, so this statement is true. Finally, when the bladder muscle contracts, the smooth muscle in the urethra relaxes to allow urine to pass. Transitional epithelium lines the bladder, facilitating its expansion and contraction.