<s>[INST] context: - Tubular reabsorption a highly selective - Some substances like glucose, AA, Na+2, H20 is absorbed maximum from upper pa of PCT As proximal tubule epithelial cells have: - Large number of mitochondria to suppo powerful active transpo processes (highly metabolic) - Have brush borders & provide extensive surface area for absorption - As glucose is reabsorbed by secondary active transpo, it is absorbed almost all by proximal convoluted tubule. Ascending limb of loop of Henle have: - Thin segment a moderate permeable to solutes increase permeable to H2O - Thick segment a viually impermeable to H2O, permeable to solutes a diluting segment of nephron. Coical collecting duct: - Contain principle cells => reabsorb Na+2 & secrete K+ - Intercalated cells => secrete / absorb H+, HCO3- & K+ ions based on PH Medullary collecting duct - Under ADH influence => Reabsorb H20 => | urine vol & |urine concentration - Permeable to urea, hence urea is reabsorbed into interstitium => increase osmolality of interstitium, helps in concentrating urine - Regulate acid base balance (by secreting H+ ions) [/INST] question: Glucose is absorbed from? | options: A: Upper pa of PCT B: Ascending limb of LOH C: Coical Collecting duct D: Medullary collecting duct | answer: A </s>