A polymer with the sequence 5' ACGTACGAATAG 3' is a:

Question

A.  polysaccharide.
B.  protein.
C.  piece of RNA.
D.  piece of DNA.

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 know about nucleic acid structure? 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

D.  piece of DNA.

Clarify Question
· What is the key concept addressed by the question?
        o The question asks you to identify a macromolecule.
· What type of thinking is required?
        o You are being asked to apply your knowledge of the representation of a macromolecule to identify it.
· What key words does the question contain and what do they mean?
        o 5’ and 3’ – these refer to the ends of a strand of nucleic acid.  The 5’ and 3’ refer to the OH groups on the ribose sugar that are not in a phosphodiester bond.
 
Gather Content
· What do you know about nucleic acid structure? How does it relate to the question?
        o The 5’ and 3’ ends are the first clue that this is a nucleic acid.
 
Consider Possibilities
· What other information is related to the question? Which information is most useful?
        o Carbohydrates or polysaccharides do not have a 5’ or 3’ end.
        o Proteins have ends that are labeled by a free amino terminus or carboxy terminus.
 
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o While all nucleic acids have a 5’ and 3’ end, these could be either RNA or DNA.  RNA has nucleotides with the abbreviations A, C, G, and U.  DNA has nucleotides with the abbreviations A, C, G, and T.  Since this sequence has T and no U it must be DNA.

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 you to apply the structure of a polymer to determine its type. If you got the correct answer, great job! If you got an incorrect answer, where did the process break down? Did you realize that the 5’ and 3’ ends meant it was a nucleic acid?  Did you notice that it had T’s and no U’s?