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What is 2nd constriction of esophagus is due to - and explain in detail?
Ans. is 'b' i.e., Arch of arorta Esophageal constrictionsNumberDistance from incisorBony levelAnatomical landmark1st2nd3rd4th15 cm (6 inches)22-5 cm (9 inches)27-5 cm (11 inches)37 -5 -40 cm (15-16 inches)C6T4T6T10At its beginning (pharyngoesophageal junction)Crossing of aortic archCrossing of left main bronchusPiercing diaphragm (at lower esophageal sphinctor)