Physiology In which pa of Henle loop is tubular fluid hypotonic with plasma/GFR? A Thin descending limb B Thin ascending segment/limb. C Thick ascending segment/limb. D Thick descending segment/limb. 💡 Explanation In which pa of Henle loop is tubular fluid hypotonic with plasma/GFR? ✓ Correct Answer: C. Thick ascending segment/limb.