Chapter 51 - Salt and Water Balance and Nitrogen Excretion - 51.3 - Invertebrate Excretory Systems Use Filtration, Secretion, and Reabsorption - 51.3 Recap - Learning Outcomes - Page 1099: 2

The cells of the Malpighian tubules actively transport uric acid, potassium ions, and sodium ions into the tubules, creating a high concentration of solutes that osmotically draws water in and flushes the tubule contents toward the gut. This mechanism is so effective that it allows some hexapod species to survive off of this reabsorption.

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