<prompt> Over half of the potassium that appears in the urine of a patient, who has ingested some potassium salts, is derived From?Glomerular filtrateSecretion by the distal tubuleReabsorption in the proximal tubuleSecretion by the loop of Henle  <response>: Secretion by the distal tubule.With a normal potassium intake filtered K which is not reabsorbed accounts for two third and secreted K counts for one-third of the excreted urinary K.However, on high potassium diet, the K secretion increases and K secretion account for about 60-65 excreted K.K secretion occurs in distal tubules and collecting duct. 