You decide to perform an experiment to test this why plants possess TRP channel agonists. You first set up batches of plants in the field WITH or WITHOUT applied capsaicin or menthol. What parameter do you then measure?

Question

A.  photosynthetic rate
B.  amount of leaf or fruit damage
C.  metabolic rate
D.  palatability to humans

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 TRP channels? 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

B.  amount of leaf or fruit damage

Clarify Question
What is the key concept addressed by the question?
        · What experiment can test why plants have TRP agonists?
What type of thinking is required?
            o This is an evaluate question because you have to use logic to evaluate potential reasons that TRP channels exist in plants, and then determine what one would measure to test that hypothesis.

Gather Content
What do you already know about TRP channels? What other information is related to the question?
        · You already know that TRP channels are found in nociceptors that respond to temperature changes. You also may recall that the first TRP receptor discovered responds to the chemical capsaicin, which is found in chili peppers, as well as to heat. Thus, when you eat spicy foods with capsaicin it provides a sensation of heat and pain. Plants have evolved to contain TRP agonists like capsaicin for the same reason some plants have evolved toxic and bitter compounds- to keep animals from eating them. In order to test if animals eat plants with either capsaicin or menthol added to them, one would need to measure leaf or fruit damage that would be caused by browsing. We humans are a strange bunch in which some of us like the sensation of heat caused by capsaicin and cool caused by menthol. Since the plants evolved long before humans did, it is sensible to test for damage caused by animals over palatability to humans.

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?
        · TRP channel agonists would not change photosynthetic rate of the plant, especially since the plants do not have receptors for the agonists (but animals do). Similarly, despite what a few health reports state, agonists like capsaicin does not have much of an overall effect of metabolic rate in humans- and besides, this experiment only mentions plants, not humans, so palatability to humans would also not be the best answer. But measuring the amount of leaf and fruit damage to the plants would test if capsaicin or menthol makes plants less palatable to non-human animals.

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?
        o Answering this question correctly depended on your ability to weigh and  judge, or evaluate, which the potential experiments to test the effects of TRP channel agonists on plants. If you got an incorrect answer, did you remember that TRP channel agonists like capsaicin bind to TRP channels to provide a sensation of a temperature change, which can be a painful and unpleasant experience that might prevent animals from eating it? Did you have trouble weighing the options that these compounds were evolutionary derived for plant survival relative to artificially selected by man for human cultivation/consumption to determine the correct answer? Did you realize that the experiment was only dealing with plants, and not humans?