Sasha Meshinchi, Staff, Microscopy and Image-analysis Laboratory, University of Michigan Medical School
The kidney is responsible for filtering waste products from the blood and removing water. Blood flows into the round green structures (glomeruli) under high pressure. The glomeruli act as filters to retain blood proteins but allow water and salt to pass into the tubules (blue, aqua, pink). From here, the filtrate takes a long and convoluted journey to reach the collecting ducts and eventually, the bladder.