This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidneys and Body Fluids, Subject name: Physiology
Aldosterone acts at: 
Select and explain. 
A. Collecting duct, B. Glomerulus, C. Proximal convoluted tubule, D. Loop of Henle
A: Collecting duct
Answer: A: Collecting duct 
Explanation: Ans. A Collecting ductRef: Ganong, 23rd ed. pg. 648* Aldosterone is secreted from adrenal cortex.* Action of aldosterone is localized to distal tubule are collecting duct.* Mechanism: Stimulates Na+K+ ATPase at basolateral end which generate gradient for movement of sodium ion from apical membrane causing an increase in sodium: reabsorption.