Question

if olfactory nerve is not present then what happen​

Answer 1

Answer:

then sensing of different smells and fragrances would not be possible as olfactory nerves are associated with smells.

Answer 2

Answer:

Some people with olfactory nerve is not present develop anosmia, but some simply have a reduced ability to smell.

This is called hyposmia. Finally, olfactory nerve disorders can cause people to develop dysosmia, where smells are mixed up so that a pleasant aroma like that of a rose might smell bad, like rotting garbage.