Question

36 This figure is from a study that looked at the 4.4 pN effect of tension on the stability of the 32 7.5 pN 11 pN 5.0 pN microtubule -kinetochore interaction. In this 28 study they were looking at purified Kinetochores that did NOT have Aurora B. For this figure they 24 20- attached a microtubule to a slide and then connected it to a kinetochore that was on a bead 16 that they could pull on using a laser. In this figure 12 Laser trap they are graphing how much the microtubule 8 1.2 pN grows over time before it looses its connection KT particle 4- with the kinetochore. The line ends when the Tension Micro- tubule connection is lost 1.7 pN a. In this figure there are three down arrows on the diagram and two up arrows. What do those 60 10 20 30 40 50 arrows indicate What might higher tensions do not have any arrows? mean that e Time (min) Many papers have suggested that tension is similarly important for actin stabilization at focal b. adhesions. i. What is a focal adhesion? . What are the similarities between actin and microtu bules that might cause them to both be stabilized by tension? iii. Given the roles of focal adhesions, why does it make sense that actin would be stabilized by moderate levels of tension at these sites? RelativeI bead position (um) elml.

Answer 1

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