Filtrate passes through the proximal convoluted tubule (PCT), loop of Henle, and distal convoluted tubule (DCT). In the proximal tubule, water, salts, and nutrients are reabsorbed. Tubular reabsorption transfers solutes and water from the renal tubules to peritubular capillaries (back into the blood). Glucose reabsorption is limited by the capacity of its transporter (if too high, glucose is excreted).
Tubular secretion transports solutes from peritubular fluid into renal tubules (into the urine). In the convoluted tubules, hydrogen ions, creatinine, and some drugs are secreted.
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