Over half of the potassium that appears in the urine of a patient, who has ingested some potassium salts, is derived from
In Normal K+ intake -
-        The proportion of K+ by filtration in urine- 2/3
-        The proportion of K+ by secretion in urine (Distal tubules and collecting duct)- 1/3
In High K+ intake-  
-        The proportion of K+ by filtration in urine- 1/3
-        The proportion of K+ by secretion in urine (Distal tubules and collecting duct)- 2/3
Glomerular filtrate
Secretion by the distal tubule
Reabsorption in the proximal tubule
Secretion by the loop of Henle