Consider the cladogram shown. Based on this cladogram, which species has the greatest number of ancestral character states?
A. 1
B. 2
C. 3
D. 4
E. 5
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?
D. 4
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 take what you already know and apply it to this unfamiliar situation.
· What key words does the question contain and what do they mean?
o A cladogram is a diagrammatic representation of a hypothesis about evolutionary relationships.
o Ancestral character traits are those original versions of a trait, before they evolved into something new.
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.
Consider Possibilities
· What other information is related to the question? Which information is most useful?
o A cladogram is a set of nested clades, characterized by their synapomorphies (shared, derived characters).
o Since the nested clades are defined by synapomorphies, the species in the innermost nested clade must share more synapomorphies than more distantly related pairs of species.
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
o The outermost species – the outgroup – must have the fewest synapomorphies and the most ancestral states (at least relative to the other species shown in this tree).
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 which species has the most ancestral characters.
o The question required you to take what you already know and apply it to this unfamiliar situation.
o Did you recognize that the outermost species in the cladogram is most distantly related to the others, and this “outgroup” has the most ancestral characters?
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Mitochondria and hydrogenosomes are similar in that they both
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You place an empty dog-food dish across the room from a puppy that then goes over to investigate the dish. You pick the dish up and ten minutes later you place it in a different part of the room, and you keep repeating this pattern. After the fifth time the puppy no longer goes over to the empty dish. Which of the following terms best describes this form of learning?
A. trial and error learning B. habituation C. classical conditioning D. operant conditioning E. imprinting 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 types of learning behaviors? 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? Reflection 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?
What prevents the epiphyseal plate from calcifying?
a. thyroid hormone b. oxytocin c. calcium channel blockers d. human growth hormone e. fat
What major advantage is conveyed by having a system of adaptive immunity?
A) It enables a rapid defense against an antigen that has been previously encountered. B) It enables an animal to counter most pathogens almost instantly the first time they are encountered. C) It results in effector cells with specificity for a large number of antigens. D) It allows for the destruction of antibodies.