Urinary System, Part 1: Crash Course Anatomy & Physiology #38
Why the open web links it
Explains the anatomy and function of the urinary system, focusing on kidney filtration and fluid balance.
Linked by 11 independent sites, 2 of them widely read in the 2026-10 crawl of the open web, including unh.edu, libretexts.org, pressbooks.pub, baker.edu, bikehike.org.