Exam 9: The Cytoskeleton and Cell Motility

___________ are recently discovered diseases that result from organelle dysfunction. Specifically, each of these diseases is a set of seemingly unrelateddisease symptoms that all result from defects in cilia.

Which of the following describes functions performed by the cytoskeleton?

Point mutations in α or β tubulin which are associated with spiral growth in Arabidopsis plants are often located at

For a long time, it was thought that cilia on most cells were unimportant or _________, despite their presence on almost all cells.This idea arosebecause the cilia on most cells are non-motile, and itwas assumed that motility was the key function of cilia.

Bardet‐Biedl syndrome (BBS)is caused by mutations in any one of a number of genes that affect protein trafficking into cilia. Persons afflicted with BBS exhibit a remarkable range of abnormalities, like polydactyly, obesity, kidney disease, etc. These disparatesymptoms are thought to reflect the function of cilia ________________.

The protein ParM has been shown to play a role in plasmid segregation during bacterial cell division analogous to the action of ___________during mitosis and is structurally similar to __________.

Researchers worked with mouse embryos that had non‐motile cilia and used a pumpto drive an artificially created flow over their surface. When theflow was leftward directed, the mice developed _____________.

The core of a cilium is called the ________.

What accounts for the decrease in the length of an entire muscle?

Which of the following molecular motors are associated with actin filaments?

Treatment of isolated spermaxonemes with 0.6 M NaClhas been shown to selectively remove the outer arms from the A microtubules of the axoneme, leaving the inner arms in place. What would be the most likely effect on the NaCl-treated axoneme when ATP was added to the medium?

The simplest and the original assumption about step size for molecular motors was that as the motor protein walked along the actin or microtubule polymer it would step__________.

In order to measure the step size of kinesin, a group of investigators attached a small silica bead to the tail of a kinesin molecule. What advantage(s)did the attached silica bead provide?

EDTA is a chemical that binds to and removes (chelates)divalent cations from solution. Treatment of isolated axonemes with EDTA leads to the removal of the inner and outer arms extending from the A microtubules of the axoneme. Which of the following statements would appear to be true based on this information?

The sperm basal body becomes ______________.

The protein FtsZ acts in the bacterial cell analogously to the ______ cytoskeleton during eukaryotic cytokinesis and is a(n)_________ homolog that is found in nearly all prokaryotic cells.

Kinesin movement along a microtubule is said to be highly ________ meaning that it can move considerable distances along an individual microtubule without falling off.

How does an actin thin filament manage to move continuously during a contraction cycle?

What blocks the myosin-binding sites on actin thin filaments in a stimulated sarcomere?

The cilia-driven flow in human and mouse embryos is detected by ___________.