<prompt> Iron is actively absorbed inStomachDuodenum and proximal jejunumLarge intestineIleum  <response>: Active absorption of iron occurs in duodenum proximal jejunum. In stomach absorption of alcohol 20 drugs like aspirin takes place. In large intestine, absorption of acids and bases, water, remainder of sodium Na and potassium K i.e. remaining because not already absorbed in the small intestine takes place. The function of ileum is mainly to absorb VitaminB12 bile salts. Ref: Guyton,11e 