General Principles of Physiology Practice Exam 2025 – Complete Test Prep

The fluid that is not filtered during glomerular filtration is returned to circulation. In the kidneys, the glomeruli filter blood, allowing water, electrolytes, and small molecules to pass into the renal tubules, while larger molecules like proteins and cells remain in the bloodstream. The fluid that does not get filtered, primarily consisting of plasma and its components, continues to circulate within the body, maintaining blood volume and pressure, and contributing to essential physiological functions.

The other options do not accurately reflect the process that occurs with the unfiltered fluid. For instance, fluid is not lost as sweat, nor is it stored in the bladder or subjected to fermentation in any significant way. The kidneys are designed to efficiently handle filtration, reabsorption, and secretion, ensuring that waste products are excreted while valuable substances are retained and returned to the body.