The bitter receptor hTAS2R38 is activated by glucosinolates found in plants such as turnips and broccoli. The gene variant a person has determines how sensitive their neurons are to these compounds. What would you predict for people who have the high-sensitivity variant of hTAS2R38?

Question

Unlike sweet, salty, sour, or umami, the "bitter" category of tastants includes wide structural variety of detected molecules. Multiple receptors are required to sense the different bitter tastants. What do they have in common? Bitter taste is thought to have evolved as a warning system for toxic compounds.

A.  They will not easily digest turnips and broccoli.
B.  They will have to eat more turnips and broccoli to get the same flavor.
C.  They will dislike turnips and broccoli.
D.  They will become allergic to turnips and broccoli.


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 taste receptors? 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

C.  They will dislike turnips and broccoli.

Clarify Question
What is the key concept addressed by the question?
        · What is the effect of high-sensitivity bitter receptors?
What type of thinking is required?
            o This is an analyze question because you have to break down the components of taste receptors and understand how changes in receptor sensitivity would change the perception of tastants and result in behavior shifts.

Gather Content
What do you already know about taste receptors? What other information is related to the question?
        · You already know that in order to detect a taste, tastants must first bind to specific receptors on the tongue and inside the mouth. Bitter tastants detect a variety of molecules and is thought to have evolved as a warning system for toxic compounds. If a receptor has high-sensitivity for bitter tastants, then bitter foods will be perceived to be extra bitter and unpalatable and people will avoid those foods.

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?
        · Individuals with the high-sensitivity variant of hTAS2R38 will be extra sensitive to bitter-tasting foods such as turnips and broccoli and will dislike them and avoid them. They will have to eat less of turnips and broccoli to get the same bitter taste, not more of them. Taste receptors have nothing to do with digestibility or allergies of foods.

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 upon your knowledge of the role of taste receptors and how changing their sensitivity would change how tastes are perceived. If you answered incorrectly, what went wrong? Did you think that high sensitivity receptors would cause individuals to eat more of bitter foods than less?