You are a landscape architect working on the grounds of a large estate. After you plant a dozen trees, the owner says, "There's been a mistake. The flowers on some of these willow trees look totally different! I specifically asked for Salix alba. You must have planted two different species." You refer to your tree guide, and read: "Salix alba - species of willow native to Europe and Asia, noted for the white undersides of leaves. Insect pollinated, dioecious. Grows 10-30m tall." How do you respond to the client?

Question

A.  "Sorry about that sir, I will dig up the wrong trees right away."
B.  "Don't worry, the trees with the smaller flowers just haven't undergone phase change yet."
C.  "Don't worry, when the shorter trees reach full size, they will grow the other kind of flower."
D.  "Don't worry, Salix alba is dioecious, meaning each tree has either male or female flowers. That is why they look different."

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 dioecious species? 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

D.  "Don't worry, Salix alba is dioecious, meaning each tree has either male or female flowers. That is why they look different."

Clarify Question
What is the key concept addressed by the question?
        · This question is asking about the cause of different appearances of individuals within a species.
What type of thinking is required?
        · Apply level:
            o You are being asked to take what you already know and apply it to an explanation of the different morphologies of two plants of the same species.

Gather Content
What do you already know about dioecious species? What other information is related to the question?
        · Dioecious means male and females are found as separate individuals..
        · Dioecious species may be sexually dimorphic, meaning that males and females have different appearances.

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?
        · Phase change occurs before flower formation, so that does not account for the different flowers.
        · Height is not a factor that influences the appearance of flowers.
        · Sexual dimorphism, or the different appearances of male and female plants of the same species, explains the differences in the plants in this example.

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?
        · Apply level:
            o Answering this question correctly depended on your ability to use the concept of a dioecious species in a new situation. If you got an incorrect answer, did you remember that dioecious species have males and females as separate individuals, or that males and females may look different from one another? Did you have trouble extending the term dioecious to determine the correct answer?