Assume that the ancestor of this phylogeny had vascular tissue and chlorophyll. If this is true, which answer lists all key traits of a ginkgo?

Question

A.  vascular tissue, needles, tree, and chlorophyll

B.  tree and seeds

C.  seeds, tree, vascular tissue, and chlorophyll

D.  needles, tree, and seeds



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 cladistics?

 

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.  seeds, tree, vascular tissue, and chlorophyll

Clarify Question
  · What is the key concept addressed by the question?
        o This question addresses cladistics.
· What type of thinking is required?
        o This question is asking you to analyze the information given, using logic, to dissect the problem and determine the answer.
· What key words does the question contain and what do they mean?
        o The ancestor of the phylogeny would be the extinct plant species at the base of the diagram.
        o Vascular tissue and chlorophyll are features that all vascular plants have.
 
Gather Content
· What do you already know about cladistics?
        o Cladistics is the method used to construct a cladogram — a graphically represented hypothesis of evolutionary relationships.
        o Only shared derived characters (synapomorphies) are useful for inferring phylogenies, and they must be contrasted to an outgroup that has the ancestral characters.
        o Each nested clade is defined by a new shared derived character. These new characters are typically labeled on the branch.
 
Consider Possibilities

· What other information is related to the question? Which information is most useful?
        o By tracing the branches from the bottom to the ginkgo branch, you can find which features the ginkgo must have.
 
Choose Answer · Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o Since the question posits that all the species have vascular tissue and chlorophyll, ginkgo has those.
        o In addition, ginkgo has seeds and is a tree – the labels shown on the branches below.
 
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 This question asked what features ginkgo has.
        o The question required you to analyze the information given, using logic, to dissect the problem and determine the answer.
        o Did you recognize that you could trace the evolution of features by moving from the bottom to the top of the tree?