NBME Form 4 ?

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NBME Form 4 ?

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pearljam59
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03/29/06 - 06:50 AM

1. Which of the following best explains the purpose of including antibiotic-resistant genes in plasmids used as vectors for cloning human genes?

A. Facilitates growth of the bacterial plasmid in human cells
B. Permits selection against bacterial cells that do not acquire a plasmid
C. Prevents the clones from growing outside the laboratory
D. Regulates expression of the inserted human gene

shocked

robin082006
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03/29/06 - 09:50 AM

B?

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huzefa
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03/29/06 - 10:57 AM

humpf!!
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05/19/06 - 05:20 AM

I choose D...can anyone explain this please?

raves
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05/26/06 - 02:05 PM

shouldn't the answer be A rolling eyes

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hlab27
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06/08/06 - 02:45 PM

When you are making vectors and want to confirm that they have been properly selected for, one usually puts an antibiotic resistant gene next to your favorite gene you are trying to clone.

This allows you to then select it. If you insert this plasmid into bacteria, it isn't 100% efficient so you can use antibiotic resistance to ensure that the bacteria picked up your favorite gene (yes, there is a very small chance that only the antibiotic part is picked up and the rest isn't but I think that is too nit picky).

So B is right.

nadiabarati

06/09/06 - 09:42 AM

raves
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06/23/06 - 01:38 PM

yes guys i was wrong B IS RIGHT FOR SURE nod

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