Your cat has fleas! You look at the ingredients in the flea control ointment, and see that it contains methoprene, a juvenile hormone analog. What does this accomplish?

Question

Many insecticides target insect hormones such as juvenile hormone or ecdysone to disrupt development. This is preferable to simply killing the insect with more broadly-acting toxins.

A.  prevents flea larvae from maturing
B.  kills juvenile fleas
C.  reinvigorates the cat's immune system, to repel the fleas
D.  forces juvenile fleas to mature early, disrupting development of reproductive organs

Clarify Question
What is the key concept addressed by the question?
What type of thinking is required?

Gather Content
What do you already know about juvenile hormone? What other information is related to the question?

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

A.  prevents flea larvae from maturing

Clarify Question
What is the key concept addressed by the question?
        · How would juvenile hormone analog effect fleas?
What type of thinking is required?
            o This is an analyze question because you have to discriminate between different mechanisms of action of a flea control compound.

Gather Content
What do you already know about juvenile hormone? What other information is related to the question?
        · Juvenile hormone is produced by a pair of glands near the brain of insects. High levels of juvenile hormone prevent the transformation to the adult and result in a larval-to-larval molt. If the level is low, metamorphosis will result.

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?
        · Let us examine the answers. Since methoprene is a juvenile hormone analog, it should produce similar effects to that of juvenile hormone, which is the inhibition of insects to reach maturity. Thus, the fleas will not die directly, but the flea larvae will not be able to metamorphose into adults that bother your cats. This hormone does not disrupt the development of flea reproductive organs or affect the cat or its immune system.

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        · Answering this question correctly depended upon analyzing each potential answer for accuracy in terms of describing the role of juvenile hormone. If you got the answer correct, great! If not, which answer did you choose? Did you think that methoprene would kill the fleas directly? Did you get confused as to the role of juvenile hormone, thinking that is sped up maturation instead of blocking it?