All of the following are part of phage conversion except

Question

A.  injection of phage gene into host.
B.  transcription and translation of phage gene.
C.  induction of phage.
D.  expression of phage gene by host.
E.  integration of phage gene to form a prophage.

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 phage conversion?
 
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.  induction of phage.

Clarify Question
· What is the key concept addressed by the question?
        o This question addresses phage conversion.
· 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.
 
Gather Content
· What do you already know about phage conversion?
        o Phage conversion refers to the conversion of a bacterium into a more dangerous, virulent form.
        o This occurs when the bacterium is itself infected with a phage that carries a virulence gene.
        o For instance, a lysogenic phage that infects V. cholerae  introduces a gene that codes for the cholera toxin. This gene, along with the rest of the phage genome, becomes incorporated into the bacterial chromosome. The toxin gene is expressed by the bacterium, converting it into a disease-causing agent.
 
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 important part of phage conversion is the insertion of the toxin gene into the host chromosome, all the steps of phage infection and integration must take place.
        o However, induction of the phage is not important. It is the inactive, prophage sitting in the chromosome that has “converted” the cell – not the activity of the phage virus itself.
 
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 The question required you to take what you already know and apply it to this unfamiliar situation.
        o Did you recognize that in phage conversion, the bacterium is converted to a more dangerous form by the insertion of a toxic phage gene into the genome?