If you want to have an idea of the molecular mechanisms involved, last year the structures of an insect odorant receptor in complex with two different odorants

If you want to have an idea of the molecular mechanisms involved, last year the structures of an insect odorant receptor in complex with two different odorants was published: https://www.nature.com/articles/s41586-021-03794-8 https://www.nature.com/articles/s41586-021-03794-8