The main substance re-absorbed into the blood in the nephron are glucose, electrolytes (sodium, potassium, chloride) and water.
Almost all the glucose is reabsorbed at the proximal tubule of the nephron. Sodium, potassium and chloride are reabsorbed at the ascending loop of Henle, and water is reabsorbed at the descending loop of Henle.
Other nutrients that are reabsorbed are magnesium, phosphates, carboxylate, bicarbonate, amino acids, some urea, proteins and oligopeptides.
Reabsorption occurs in two steps namely active or passive extraction of sustances from the fluid in the tubules of the nephron, and into the interstitium , then transport of these substances from interstitium and into the bloodstream.
Answer:
In my opinion it is the main control center of the body.
