Organic nutrients glucose amino acids all reabsorbed Water ions continuously

Organic nutrients glucose amino acids all reabsorbed

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Organic nutrients (glucose, amino acids) all reabsorbed Water, ions continuously regulated
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Methods of Reabsorption Active Transport: ATP used to move molecules across membrane. Sodium Secondary Active Transport: when Active Transport of one molecule helps to move another molecule across a membrane (via a co- transporter). Glucose, amino acids, vitamins Passive Transport: a concentration gradient drives diffusion of a molecule across a membrane. Water, ions
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Passive Transport of Water Obligatory water reabsorption Facultative water reabsorption Water reabsorbed regardless of state of over- or under- hydration of body Location: PCT, nephron loop (descending limb) Water reabsorption that depends on ADH (hormone- controlled) Location: Collecting duct
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Hormonal Regulation of Tubular Reabsorption Reabsorption of water and solutes only controlled in DCT and Collecting Duct. Hormone Function Antidiuretic Hormone (ADH) During dehydration, ADH increases -> decreases urine output by causing more reabsorption of water in CD (opposite in over-hydration) Aldosterone Increases Na + reabsorption in DCT & CD Goal is to increase blood volume and pressure Atrial Natiuretic Peptide (ANP) Decreases Na + reabsorption in CD Opposite to Aldosterone Parathyroid Hormone (PTH) Increases reabsorption of Ca 2+ in DCT
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