The Accompanying Figure Shows Data from an Experiment in Which

question 26

Multiple Choice

The accompanying figure shows data from an experiment in which researchers measured how far dynein (a motor protein) traveled in the presence and absence of dynactin (another type of protein) . The y-axis shows the percent of the time that the researchers observed either dynein or dynein + dynactin "walking" a certain distance on a microtubule. What can you conclude from these data?

• A) The addition of dynactin caused dynein to travel farther along the microtubule.
• B) Dynein traveled farther in the absence of dynactin.
• C) A higher fraction of the dynein proteins were motile in the absence of dynactin.
• D) Dynactin would have the same effects on dynein movement on microfilaments.

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Definitions:

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A condition characterized by the narrowing of the coronary arteries, leading to decreased blood flow to the heart.

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Bloodstream

The flowing blood as it circulates through the heart, arteries, capillaries, and veins in the body, delivering essential nutrients and oxygen.