This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'Where in the kidney does active reabsorption of sodium ions occur \nSelect and explain. \nA. Collecting duct, B. Distal tubule, C. Ascending limb of Henle, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Other than at thin descending limb of the loop of Henle, all other sites of tubule Na+\xa0are reabsorbed by various mechanisms.\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0Proximal tubule- 60-70%\n\nNa+- H+\xa0exchange\nNa+- Glucose co-transport\nNa+- amino acid co-transport\nNa+\xa0unitransport\n\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0The thick ascending limb of the loop of Henle - 30%\n\nNa+- 2Cl-- K+\xa0co-transport\n\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0Early distal tubule- 7%\n\nNa+- Cl-\xa0co-transport\n\n-\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0Late distal tubule and collecting duct - 3%\n\nENaC channels', 'role': 'assistant'}]