Conjugation in most ciliates involves a series of steps that leads to increased genetic diversity. Which one of the following choices is not one of those steps?

Question

A.  mitosis of a haploid nucleus
B.  mitosis of a diploid nucleus
C.  meiosis of a haploid nucleus
D.  meiosis of a diploid nucleus
E.  sexual reproduction

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 mitosis and meiosis? How does it relate to the question?

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.  meiosis of a haploid nucleus

Clarify Question
· What is the key concept addressed by the question?
        o This question asks you to determine which steps are part of conjugation. One of the options is not part of conjugation.
· What type of thinking is required?
        o This question is an “apply” question. You need to use your knowledge of conjugation, mitosis, and meiosis to answer the question.
 
Gather Content
· What do you already know about mitosis and meiosis? How does it relate to the question?
        o Mitosis duplicates a nucleus, so a diploid nucleus would produce two diploid nuclei.
        o Meiosis duplicates, then divides a nucleus, so a diploid nucleus would produce four haploid nuclei.
        o Do both of these occur in conjugation? When do they occur?
 
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o Go through each option and see first whether it makes sense. Then, think about whether it occurs in conjugation.
 
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 steps occur during conjugation and which do not.
        o If you got the correct answer, great job!
        o If you got an incorrect answer, where did you get stuck?
            · Meiosis cannot happen to a haploid nucleus because there is nothing to divide. Meiosis can only happen to a nucleus that has 2, 4, 6, etc. copies of the chromosomes.