Answer:
glomerular filtration, reabsorption along the proximal tubule and the loop of Henle, and bidirectional transport (secretion and reabsorption)
Explanation:
Studies on single tubules show that potassium excretion is mediated by three processes: glomerular filtration, reabsorption along the proximal tubule and the loop of Henle, and bidirectional transport (secretion and reabsorption) in the initial and cortical collecting tubul.
