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Questions and Answers
What is the result of all the monomers within an actin filament being pointed in the same direction?
What is the result of all the monomers within an actin filament being pointed in the same direction?
Which molecule does an actin monomer bind before being incorporated into a filament?
Which molecule does an actin monomer bind before being incorporated into a filament?
What kind of enzyme is actin, as mentioned in the text?
What kind of enzyme is actin, as mentioned in the text?
Which end of an actin filament incorporates monomers at a rate about 10 times faster than the other end?
Which end of an actin filament incorporates monomers at a rate about 10 times faster than the other end?
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What occurs much more rapidly in actin filament formation after the initial nucleation event?
What occurs much more rapidly in actin filament formation after the initial nucleation event?
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What defines actin as a major protein in every eukaryotic cell?
What defines actin as a major protein in every eukaryotic cell?
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What is the characteristic of kinesin that allows it to walk along a microtubule for considerable distances without falling off?
What is the characteristic of kinesin that allows it to walk along a microtubule for considerable distances without falling off?
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What is the primary function of kinesin-mediated organelle transport?
What is the primary function of kinesin-mediated organelle transport?
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How does the movement of cytoplasmic dynein along a microtubule compare to that of most kinesins?
How does the movement of cytoplasmic dynein along a microtubule compare to that of most kinesins?
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What is the structure of a cytoplasmic dynein molecule?
What is the structure of a cytoplasmic dynein molecule?
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What is the effect on the phenotype of a cell when a member of the kinesin superfamily is absent?
What is the effect on the phenotype of a cell when a member of the kinesin superfamily is absent?
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Which of the following is a key characteristic of the 'hand-over-hand' movement mechanism of kinesin?
Which of the following is a key characteristic of the 'hand-over-hand' movement mechanism of kinesin?
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What are the structural characteristics of tubulin subunits within a microtubule?
What are the structural characteristics of tubulin subunits within a microtubule?
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What is the primary function of microtubule-associated proteins (MAPs)?
What is the primary function of microtubule-associated proteins (MAPs)?
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Which of the following statements about the microtubule-associated protein tau is correct?
Which of the following statements about the microtubule-associated protein tau is correct?
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What is one of the primary functions of microtubules in cells?
What is one of the primary functions of microtubules in cells?
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How does the distribution of microtubules contribute to cell shape?
How does the distribution of microtubules contribute to cell shape?
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What is the significance of the polar nature of microtubules?
What is the significance of the polar nature of microtubules?
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What happens to the GDP molecule after it is formed during the hydrolysis of GTP in the assembled microtubule?
What happens to the GDP molecule after it is formed during the hydrolysis of GTP in the assembled microtubule?
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What is the purpose of the nucleotide exchange from GDP to GTP during the disassembly of tubulin dimers?
What is the purpose of the nucleotide exchange from GDP to GTP during the disassembly of tubulin dimers?
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What is the structural difference between GTP-tubulin and GDP-tubulin that affects their ability to fit into a protofilament?
What is the structural difference between GTP-tubulin and GDP-tubulin that affects their ability to fit into a protofilament?
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What is the role of the open sheet of tubulin-GTP subunits at the tip of the growing microtubule?
What is the role of the open sheet of tubulin-GTP subunits at the tip of the growing microtubule?
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What is the mechanism that leads to the catastrophic shrinkage of the microtubule?
What is the mechanism that leads to the catastrophic shrinkage of the microtubule?
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Which of the following is NOT a dynamic process that the cell can reorganize its actin cytoskeleton for?
Which of the following is NOT a dynamic process that the cell can reorganize its actin cytoskeleton for?
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What is the primary function of conventional (type II) myosins?
What is the primary function of conventional (type II) myosins?
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What is the defining characteristic of the head domain of all myosin proteins?
What is the defining characteristic of the head domain of all myosin proteins?
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How do conventional (type II) myosins differ from unconventional myosins?
How do conventional (type II) myosins differ from unconventional myosins?
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What is the directionality of movement of conventional (type II) myosins along actin filaments?
What is the directionality of movement of conventional (type II) myosins along actin filaments?
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What is the primary function of the tail domains of myosin proteins?
What is the primary function of the tail domains of myosin proteins?
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