Vibrio cholerae produces a toxin that destroys the intestinal epithelium. This leads to massive diarrhea; the diarrhea can kill the human via dehydration but helps the bacteria spread and colonize other humans. What is this relationship?

Question

A.  Mutualistic
B.  Commensalistic
C.  Symbiotic
D.  Atavistic

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 symbioses? 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.  Symbiotic

Clarify Question
· What is the key concept addressed by the question?
        o The question describes the relationship Vibrio cholera has with the humans it infects. It then asks you to pick the word that best describes this relationship.
· What type of thinking is required?
        o This question is an “apply” question, so it is asking for you to take a concept you already know (relationships prokaryotes have with eukaryotes) and apply it to a new scenario to solve the problem.
 
Gather Content
· What do you already know about symbioses? How does it relate to the question?
        o A symbiosis is when two organisms live in very close contact (e.g., fungi that live inside a plant). These relationships can be grouped into three categories:
            · mutualism – both members of the symbiosis benefit (e.g., the bacteria in cow intestines that help the cow digest grass)
            · commensalism – one member benefits but does not harm the other (e.g., moss or lichen growing on the bark of a tree)
            · parasitism – one member benefits at the expense of the other member (e.g., malaria reproduces inside the cells of a human but this makes the human very sick)
· What other information is related to the question? Which information is most useful?
        o Atavism is when an organism has a trait similar to a distant ancestor, even though a more recent ancestor had a different trait. For example, the common ancestor of all flowering plants was woody, but grasses and other species lost the ability to produce wood. This makes them look more similar to non-flowering plants such as ferns.
 
Choose Answer · Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        · You can approach this question in two ways:
            · Cross out the answers that are obviously false. Assess the remaining answers. Which one is the best description of the relationship Vibrio cholera has with humans?
            · Cover up the options and answer the question like it is short answer. It might be best to write two or three possible answers. Then, look at the options. Is your answer among the options? If not, cover up the options, re-read the question, and write another 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?
        o This question asked you to determine which word best describes the relationship between Vibrio cholera and humans.         o If you got the correct answer, great job!
        o If you got an incorrect answer, where did the process break down?
            · The best description of the relationship between Vibrio cholera and humans is “parasitic”, but that isn’t one of the options. However, parasitism is a type of symbiosis, so the relationship is also symbiotic.
            · If you started by crossing out the incorrect answers, you would first rule out Atavistic, which doesn’t describe a relationship at all. Humans are definitely harmed by Vibrio cholera, so the relationship wouldn’t be mutualistic or commensalistic. The only option left is symbiotic.