Which is the correct sequence of tubular segments that filtrate passes through after leaving the glomerulus?

Which is the correct sequence of tubular segments that filtrate passes through after leaving the glomerulus?

• A. Proximal convoluted tubule → Loop of Henle → Distal tubule → Collecting duct
• B. Loop of Henle → Proximal convoluted tubule → Distal tubule → Collecting duct
• C. Collecting duct → Distal tubule → Loop of Henle → Proximal convoluted tubule
• D. Distal tubule → Collecting duct → Proximal convoluted tubule → Loop of Henle

Answer: (A)

After leaving the glomerulus, filtrate first enters the proximal convoluted tubule where most reabsorption of water, ions, and nutrients occurs. It then moves into the Loop of Henle, where the descending limb concentrates the filtrate by water reabsorption and the ascending limb reabsorbs salts, creating the medullary gradient. Next is the distal convoluted tubule, where additional regulated reabsorption and secretion adjust solute and water balance under hormonal control. Finally, the filtrate enters the collecting duct system, where final water reabsorption is modulated by vasopressin and the urine is formed.

After leaving the glomerulus, filtrate first enters the proximal convoluted tubule where most reabsorption of water, ions, and nutrients occurs. It then moves into the Loop of Henle, where the descending limb concentrates the filtrate by water reabsorption and the ascending limb reabsorbs salts, creating the medullary gradient. Next is the distal convoluted tubule, where additional regulated reabsorption and secretion adjust solute and water balance under hormonal control. Finally, the filtrate enters the collecting duct system, where final water reabsorption is modulated by vasopressin and the urine is formed.