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: When it interacts with ryanodine receptors, this element upregulates its own release, and this compound forms the cell plates of coccolithophores. Stimulation of Gq ("g-sub-q") opens a channel that allows for this ion's movement, and proteins that bind this ion have an EF hand motif. Cellular concentrations of this ion are regulated by IP3. Parafollicular cells of the (*) thyroid produce a compound that reduces the concentration of this ion in blood, and its intestinal absorption requires vitamin D. This ion interacts with Troponin to stimulate muscle contraction, and the lumens of sarcoplasmic reticula have high concentrations of this ion. For 10 points, name this divalent cation that is stored in bones.

Answer: Science

Question: Slogans which became popular in this country included "we don't want to be slaves anymore" and "down with the government, down with the police." This country was home to the underground Christian organization Young Congregation, which helped instigate an event whose nine demands were issued by the Bitterfeld committee, the most influential of the workers' councils which emerged here. People in this country received boxes containing peas, flour, milk, and lard that were known as (*) Eisenhower Packages. After this country announced the New Course program, replacing Constructing Socialism, and including a ten percent increase in production quotas, workers walked out onto Stalin Alley. In this country, where the play The Plebeians Rehearse the Uprising takes place, Soviet tanks were deployed to end a 1953 popular uprising. For 10 points, identify this country which erupted into mass demonstrations against Walter Ulbricht's regime.

Answer: History

Question: This opera's premiere at La Scala was marred by the false exclamation that the lead soprano, Rosina Storchio, was pregnant with Arturo Toscanini's child when her dress blew in the wind. It's not Lakme, but this opera sees the title character and her servant sing the Flower Duet while decorating a house. An aria in this opera tells of standing on a hill and predicting the appearance of a (*) white ship. The love duet "Bimba, bimba" is sung in this opera, whose title character also sings "Un bel di" as she awaits the return of her husband in this opera. At the end of this opera, Pinkerton rushes in a moment too late to save his wife Cio-Cio San from committing suicide with her father's knife. For 10 points, name this Giacomo Puccini opera set in Japan.

Answer:
Fine Arts