OBJECTIVE LIFE SCIENCE
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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an increase in the range of locations where bedbugs live
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an increase in pesticide resistance in other insects living near bedbugs
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an increase in the number of bedbugs with gene mutations coding for pyrethrin resistance
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an increase in the number of bedbugs with specialized cell receptors for pyrethrin
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Detailed explanation-1: -In 2010, however, it was observed that many bedbug populations were not affected by pyrethrin. Which of the following is the most likely reason pyrethrin is no longer effective against some bedbugs? the extremes of the population have a lesser chance to survive.
Detailed explanation-2: -A classic example is the house fly. Populations of this insect that became resistant to DDT in the 1950s, also exhibited resistance, with no previous exposure, to pyrethroid insecticides used decades later. DDT and pyrethroids have the same MOA. This phenomenon is known as cross-resistance.
Detailed explanation-3: -There are two basic resistance mechanisms existing in pests, i.e., target site resistance and metabolic resistance. During resistance of target site, the specific binding site of an insecticide is modified (mutated) and/or lost, which makes the target site incompatible for activation.
Detailed explanation-4: -Subsequent uses of the pesticide increase the proportion of less-susceptible individuals in the population. Through this process of selection, the population gradually develops resistance to the pesticide. Worldwide, more than 500 species of insects, mites, and spiders have developed some level of pesticide resistance.