Question

which is the proper order of structures that contact the substances removed from the blood?
nephron → urethra → bladder → ureter
urethra → ureter → bladder → nephron
nephron → ureter → bladder → urethra
urethra → bladder → ureter → nephron

Explanation:

The nephron is the functional unit of the kidney where filtration occurs. The filtrate (urine) then travels through the ureter to the bladder for storage. Finally, urine is excreted through the urethra.

Answer:

nephron → ureter → bladder → urethra (the third option)