When an appropriate odor molecule (odorant) binds to its receptor, depolarization of the membrane occurs. Does this mean a signal goes directly to the brain and the odor is perceived by the brain?
A)Yes, because if an EPSP is generated, then the cell was depolarized and the signal was sent to the brain.
B)Yes, because if an EPSP is generated, then the match between the molecule and its receptor was appropriate and the signal was sent to the brain.
C)No, because although each EPSP is sent to the brain, the brain doesn't perceive the odor or taste unless an appropriate number of EPSPs are sent by the odor sensory cells.
D)No, because enough of the appropriate molecules must bind to the receptors for a summed response from all the EPSPs to generate an action potential that is transmitted to the brain.

Question

Quizplus · Accepted Answer

While the depolarization of the membrane is necessary for the generation of EPSPs, it takes enough of the appropriate odor molecules binding to their receptors to generate a summed response of EPSPs that will generate an action potential to be transmitted to the brain. Therefore, the correct answer is D.

When an Appropriate Odor Molecule (Odorant) Binds to Its Receptor