In mammals, olfactory neurons ?A. are dying and being renewed throughout life. B. are a misnomer- they are really receptor cells that do not fire action potentials C. have a single non-motile cilia D. generally express 2-4 olfactory receptors QUESTION 7 1 points ✓ Saved Why is it thought that 7TM olfactory receptors have larger amino acid diversity in the “barrel of staves” compared to other 7TM receptors? A. they are an older gene family B. there is more evolutionary selective pressure C. This allows the different receptors to form pockets to bind different odorants. D. None of the above