It is thought that there are hundreds of different olfactory receptors, each encoded by a different gene and each recognizing different odorants. Each of the hundreds of receptors are encoded by a specific gene . If your DNA is missing a gene or if the gene is damaged, it can cause you to be unable to detect a certain smell. For example, some people have no sense for the smell of camphor. When you smell many fruits or flowers, what you are smelling is esters evaporating from the fruit or flower.
Esters are organic molecules.
For example, the ester that gives a banana its smell is called isoamyl acetate and the formula for it is CH 3 COOC 5 H 11 . The primary smell of an orange comes from Octyl acetate, or CH 3 COOC 8 H 17 . Inc. All rights reserved. Please Click Here for a complete list of previously answered questions. If you would like to ask a question you can click here .