This image shows a section of the human kidney, showing the simple cuboidal epithelium, which lines the renal tubules. These cube-shaped cells have central, round nuclei and form the walls of structures like the proximal and distal convoluted tubules, which are key in filtration and reabsorption. Also visible are the lumen of the tubules, where filtered fluid passes, and nearby renal interstitium, which supports the tubules. Although not labeled here, you may also spot cross-sections of glomeruli and peritubular capillaries in a more detailed field. These features work together to maintain fluid and electrolyte balance in the body.