You walk into your house and smell a weak, foul odor. You walk from room to room and the odor becomes stronger, until eventually it becomes extremely powerful and you find a sandwich you had dropped behind the couch that had rotted. Which of the following are occurring in your olfactory receptor cells as you search out the source of the odor?
A) larger hyperpolarizing receptor potential
B) larger depolarizing receptor potential
C) decreased levels of cAMP
D) increased amplitude of action potentials

Question

Quizplus · Accepted Answer

As the odor becomes stronger, there would be an increase in the concentration of odorant molecules binding to the receptors on the olfactory receptor cells, leading to a larger depolarizing receptor potential. This larger depolarization would lead to an increased frequency of action potentials in the olfactory receptor cells, allowing for better perception and localization of the odor source. Option A is incorrect because hyperpolarization would decrease the excitability of the receptor cells and decrease sensitivity to the odorant molecules. Option C is also incorrect as cAMP plays a role in olfactory transduction, but its levels do not necessarily change during odor perception. Lastly, option D is incorrect because the amplitude of action potentials does not change during odor perception.

You Walk into Your House and Smell a Weak, Foul