In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Q: One protein that binds to this protein also binds to proline-rich sequences in the membrane proteins Vasp and Mena, and another is knocked out in the singed mutant. Phosphatidyl-inositol-4,5-bisphosphate regulates the binding of vinculin to both talin and this other protein, whose function is performed by nematode Major Sperm Protein in the only (*) eukaryotic cells known to lack one form of it. In addition to the aforementioned profilin and facsin, severin and gelsolin bind to this protein and sever it. Two toxins often used to study it are cytochalasins and phalloidin. Thymosin 4 sequesters this protein, which undergoes treadmilling because the critical concentration at its (+) and (-) ends is not the same. This protein consists of G monomers which polymerize into F filaments, which make up the microfilaments of the cytoskeleton. For 10 points, name this protein that forms cross-bridges with myosin in muscle cells.

A: Science
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Q: In the Corey-Bakshi-Shibata catalyst, an atom of it is attached to a pyrrole ring, an oxygen atom, and a toluene group. This element's acids are combined with amines and ketones in the Petasis reaction and in combining alkyl halides through the Suzuki coupling. Complexes containing it are called sido or arachno according to Wade's rules, and a more famous reaction using it is sometimes named for Herbert Brown. Mined from the ore Uletite, its silicate was once used in making hard glass for manufacturing laboratory equipment. For 10 points, name this element that participates in an anti-markonikov addition reaction to alkenes, with atomic number 5 and symbol B.

A: Science
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Q: President Carter once recommended sanctions on this country for not exporting more oil to the U.S. during the late 1970s to make up for dwindled American reserves due to the lingering aftereffects of the Arab oil embargo during the early 1970s. An earthquake on Leap Year Day in 1960 in Agadir caused the deaths of more than twelve thousand people. Until his death due to natural causes in 1999, its head of state adamantly claimed to be a direct descendant of the prophet Mohammed. It is one of the worlds largest suppliers of phosphates. This nation still has not regained control of the enclaves of Ceuta and Melilla, nor has it relinquished its territory annexed since 1976 with a territorial capital of El Aaiun and with Polisario guerillas roaming the desert regions. For ten points, name this nation, independent since 1956.

A:
History
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