Question

why glottis is covered by epiglottis

Answer 1

The glottis is guarded by epiglottis because it prevents the entry of food in wind pipe. If the food enters wind pipe, then it chokes it, leading to the death of the person. 

Answer 2

The glottis is guarded by epiglottis because it prevents the entry of food in wind pipe. If the food  enters wind pipe, then it chokes it, leading to the death of the person.

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