What would be strong evidence to suggest a protist is phototrophic?

Question

A.  Many lysosomes
B.  Locomotion via several flagella
C.  The presence of chloroplasts
D.  Silicon dioxide cell walls
E.  A benthic lifestyle

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 the nutritional strategies of protists? How does it relate to the question?
· 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 presence of chloroplasts

Clarify Question
· What is the key concept addressed by the question?
        o This question gives you five characteristics of a protist. You need to determine which characteristic would tell you that the protist is phototrophic.
· What type of thinking is required?
        o This question is an “evaluate” question, so it is asking you to judge which of the statements provides the best evidence of phototrophy. All of the statements could be correct, but only one provides evidence of phototrophy.
 
Gather Content
· What do you already know about the nutritional strategies of protists? How does it relate to the question?
        o Protists can be autotrophic, heterotrophic, or mixotrophic.
        o Autotrophs get their energy from photosynthesis or chemosynthesis. An organism that does photosynthesis would be called “phototrophic”. What characteristics would you expect in a protist that does photosynthesis?
        o Heterotrophs get their energy by eating things, but single-celled organisms don’t eat things the way we do. An amoeba is an example of a heterotrophic protist. How does an amoeba get food?
        o Mixotrophs, such as Euglena, can use either photosynthesis or heterotrophy.
· What other information is related to the question? Which information is most useful?
        o Think of the different protists that do photosynthesis (for example, green algae and euglena). Is there a trait they all share?
 
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o You know phototrophy is a nutritional strategy, and that it involves getting energy through photosynthesis. Which characteristic would be essential for a protist that wants to do photosynthesis? Other statements could still be true about the organism, but one of them is essential.
 
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 determine which characteristics would be essential for an organism that is phototrophic.
        o If you got the correct answer, great job!
        o If you got an incorrect answer, where did you get stuck?
            · This was an “evaluate” question, which required you to weigh and judge whichpiece of evidence would convince you that the protist is phototrophic. Some protists, like red algae, are able to do photosynthesis with a different organelle, but most use chloroplasts. Of the options you were given, “the presence of chloroplasts” is the best answer because that organelle would allow a protist to do photosynthesis.