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: A namesake protein component of this structure is detected by Toll-like Receptor 5. Tg737, whose mutation causes polycystic kidney disease in mice, is responsible for transport within this structure, which is also dependent upon complexes of IFT proteins. Y. Pestis uses a structure homologous to these to inject virulence factors into host cytoplasm, known as the Type III secretory system. They have a P, L, and MS ring in gram-negative bacteria, and in all organisms their central body is called the axonene. In Eukaryotes, they contain a 9+2 set of microtubules around a central pair and use dyenin and ATP hydrolysis to power their whipping motion. Similar to cilia, for 10 points, name these projections used by cells to swim.

A: Science
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Q: Coombs tests detect these bodies bound to erythrocytes, and a technique that uses these entities is ELISA. These molecules have a namesake fold, in which two beta sheets are held together by amino acid charges. These adaptable molecules can somatically recombine in a process called V(D)J recombination and are also capable of changing isotype by altering conformation of their heavy chains. Like enzymes, they operate via a a so-called "lock-and-key" mechanism, as verified by Linus Pauling. FTP, name these characteristically y-shaped immune molecules exploited in vaccination and produced by B cells in response to specific antigens.

A: Science
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Q: Philip of Cognac was the only and illegitimate son of this man, who is buried at the Abbey of Fontevraud. His engagement with Alix, countess of the Vexin did not result in marriage, as allegedly his own father took her as mistress; he married Berengaria of Navarre instead. That marriage took place in Limassol after this man conquered Cyprus from Isaac Comnenus. He came to the rescue of his sister, Queen Joan, in Sicily, and forced Tancred to release her and reinstate her dowry. Leopold V of Austria imprisoned him in Durnstein, and both his brother and Philip II of France plotted to keep him prisoner; instead, he was released on a huge ransom and returned to England. He died in 1199, allegedly in the arms of his mother, Eleanor of Aquitaine. FTP Name this son of Henry II and brother of King John, leader of the 3rd crusade

A:
History
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