Final answer:
The fluid in the nephron becomes urine by the time it reaches the collecting tubules. The final processes of absorption and concentration occur in the collecting ducts, preparing the urine to be expelled from the body.
Step-by-step explanation:
By the time the fluid in the nephron reaches the collecting tubules, it becomes urine. This process is part of the kidneys' function to filter blood and produce urine as a form of waste elimination. During the journey through the nephron, the filtrate is processed in the Bowman's capsule, travels through the proximal and distal convoluted tubules, the loop of Henle, and ultimately reaches the collecting ducts.
It is here in the collecting ducts that the final concentration occurs, where water is reabsorbed, and the fluid that remains is urine. This urine then enters the ureters and is eventually stored in the urinary bladder.
The statement 'The collecting duct empties into the distal convoluted tubule' is false, as the collecting duct actually receives urine from the distal end of the renal tubule, not the other way around. Additionally, the semen is a completely different fluid from urine and is involved in the reproductive system, not the urinary system.