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.
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Question: 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.

Answer: Science


Question: Notably, one of these entities is absent in the Leishmania mexicana GPI8 protein, and abnormally low numbers of pericytes occur if one is missing from PDGF. Binding of 14-3-3 proteins to GABAB ["Gabba-sub-bee"] receptors does not occur when two arginines are mutated to alanine in one of these entities, which also binds to the COPI complex. They are usually C-terminal signals, and a common mammalian one consists of the amino acids lysine, aspartate, gluatamate, and leucine, or KDEL. hnRNP C proteins contain one of them that allows them to override nuclear export signals. For 10 points, name these signals important in directing proteins to the correct membranes, most often used to prevent a protein's export from the endoplasmic reticulum. 

Answer: Science


Question: One president of this country was scandalized when he allowed the warship Esmerelda to fly its flag. That leader was succeeded by a man known as the "Old Battler," Eloy Alfaro, who led the liberal revolution here in opposition to Gabriel Garcia Moreno; both of those leaders were assassinated and journalist Juan Montalvo bragged that his pen killed the latter. The populist Jose Velasco Ibarra served as its president five times in the 20th century. Its independence came with the defeat of the general Melchor Aymerich by Sucre in 1822 at the Battle of Pichincha, after which it briefly became the southern district of Gran Colombia. More recently, its leaders have resolved border disputes with neighboring president Alberto Fujimori. FTP, name this South American country home to Cotopaxi, Guayaquil, and Quito.

Answer:
History