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Old 10-31-2011
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Molecular Which molecule is responsible for rapid collapse of microtubules?

While studying intracellular transport, a researcher discovers that microtubules play a key role. She notes that while the microtubules assemble slowly, they collapse very quickly. Which complex is responsible for the rapid collapse?

A. β subunit-GDP complexes
B. β subunit-ATP complexes
C. α subunit-ADP complexes
D. α subunit-GDP complexes
E. β subunit-ADP complexes
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Old 11-01-2011
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While studying intracellular transport, a researcher discovers that microtubules play a key role. She notes that while the microtubules assemble slowly, they collapse very quickly. Which complex is responsible for the rapid collapse?

A. β subunit-GDP complexes
B. β subunit-ATP complexes
C. α subunit-ADP complexes
D. α subunit-GDP complexes
E. β subunit-ADP complexes

"Not sure though"
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Old 11-01-2011
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The correct answer is A.
While microtubules are composed of α and β-tubulin dimers, it is the β-GTP form that is stable. As the energy in GTP is consumed, β-GDP forms. This is highly unstable and leads to rapid microtubule collapse.
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Old 11-01-2011
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A!

Good question ricko335, I just studied this topic briefly today really didnt think it was high yield- clearly that means I have to be more careful about what I think is high yield.
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