Climbing plants, such as vines, rely on touch to navigate and develop tendrils that coil around objects they encounter. Roots also rely on touch to navigate their way through the soil. When roots come into contact with an object, they generally grow in a direction away from the object. Based on this information, which of the following statements is true?

Question

A.  Both tendrils and roots are displaying thigmonastic responses to an object in the environment.
B.  The tendrils are displaying a thigmonastic response while the roots are displaying a thigmotropic response.
C.  The tendrils are displaying a positive thigmotropic response while the roots are displaying a negative thigmotropic response.
D.  The tendrils are displaying a thigmotropic response while the roots are displaying a thigmonastic response.
E.  The tendrils are displaying a negative thigmotropic response while the roots are displaying a positive thigmotropic response.

Clarify Question
· What is the key concept addressed by the question?
· What type of thinking is required?
· What key words does the question contain and what do they mean?

Gather Content
· What do you already know about plant responses to their environments? How does it relate to the question?

Consider Possibilities
· What other information is related to the question? Which information is most useful?

Choose Answer
· Given what you now know, what information and/or problem solving approach 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.  The tendrils are displaying a positive thigmotropic response while the roots are displaying a negative thigmotropic response.

Clarify Question
· What is the key concept addressed by the question?
        o This question is asking you to assess the type of growth responses exhibited by a climbing plant.
· What type of thinking is required?
        o This question is asking you to evaluate the type of growth responses shown by a climbing plant.
· What key words does the question contain and what do they mean?
        o Tendrils, which is a coiling, thin extension of a plant.
        o Climbing plant, which is a plant with a relatively weak stem that uses other structures for support.

Gather Content
· What do you already know about plant responses to their environments? How does it relate to the question?
        o In a thigmonastic response the direction of the growth is the same regardless of the direction of the stimulus.
        o Thigmotrophic growth occurs directionally.

Consider Possibilities
· What other information is related to the question? Which information is most useful?
        o Neither the tendrils or the roots are displaying a thigmonastic response.

Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o Both the tendrils and roots are thigmotrophic. Growth toward the stimulus would be positively thigmotropic. Growth away from the stimulus would be negatively thigmotropic.

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?
· Evaluate level:
This question asked you to evaluate the growth of the roots and stems of a plant.  Answering this question correctly depended on your ability to evaluate the specific growth patterns of the stem and roots. If you got the correct answer, well done! If you got an incorrect answer, where did the process break down? Did you remember that thigmotrophic growth occurs in a certain direction, or the criteria to compare positive versus negative thigmotrophism includes analysis of whether growth occurs toward or away from a stimulus? Did you have trouble weighing the merits of the growth patterns to determine the correct answer?