Passage IV
Certain odorants (airborne chemical compounds) can stimulate a change in the electrical activity of the olfactory neurons in the antennae of the moth Manduca sexta. The change in the electrical activity of an antenna in the presence of an odorant can be detected as an increase in the antenna’s voltage relative to its voltage in the absence of odorants. The figure below shows the average change in antennal voltage for adult female M. sexta that were exposed to each of 5 odorants at each of 4 concentrations.
22. As the odorant concentration increased from 1 mg/L through 100 mg/L, the average change in antennal voltage:
Your Answer is
Correct Answer is J
Explanation
Look at the picture, for For some substances, it follows the abscissaconcentrationaverage change in antenna voltageaverage change in antenna voltage is also added. But for propylacetone, The ordinate first increases and then decreases. So