Final answer:
In the distal convoluted tubule (DCT), between 60-80% of potassium is reabsorbed into the bloodstream, a process influenced by aldosterone levels.
Step-by-step explanation:
In the distal convoluted tubule (DCT), 60-80% of the potassium in the tubular fluid is reabsorbed. The reabsorption process in the DCT is part of the kidney's function to recover water and electrolytes. Aldosterone plays a key role by increasing the amount of Na+/K+ ATPase in the basal membrane of the DCT and collecting duct, facilitating potassium reabsorption and movement of Na+ out of the lumen.
This movement of Na+ creates a negative charge, further encouraging reabsorption by promoting the movement of Cl- into the interstitial space. Ultimately, the peritubular capillaries receive the reabsorbed substances, returning them to circulation.