chemical senses: smell

olfactory epithelium

specialized cells in superior concha of nose, 10-20 million olfactory receptors

sniff to spiral and churn the air up to the olfactory epithelium

why do we sniff?

olfactory epithelium

specialized cells in superior concha of nose, 10-20 million olfactory receptors

sniff to spiral and churn the air up to the olfactory epithelium

why do we sniff?

olfactory receptor cells

sensory neurons that detect odorants by means of receptors on cilia

supporting cells

surround olfactory cells, provide stability & shape

basal cells

stem cells for olfactory receptors

10,000

how many odors can we detect?

declines

what happens to the ability to smell as you age?

Right- has more emotional connections

which nostril has a more extreme reaction to scent?

Left- logic & reasoning

which nostril has a more accurate sense of smell?

ethyl mercaptan

garlicky egg smell used to make natural gas smell, not everyone can smell it (genetics)

anosmia

loss or reduction of smell sensation— can be congenital (under development of olf bulb) or caused by trauma (crushing of cribiform plate, toxic chemicals destroy basal cells)

secondary messenger system, increased ion permeability, AP

what is the pathway of smell?