Problem: Serological methods are highly sensitive, specific and often extremely rapid tests used to identify microorganisms. These tests are based upon the ability of an antibody to bind specifically to an antigen. The antigen, usually a protein or carbohydrate made by an infectious agent, is bound by the antibody. This binding then sets off a chain of events that can be visibly obvious in various ways, dependent upon the test. For example, "Strep throat" is often diagnosed within minutes, and is based on the appearance of antigens made by the causative agent, S. pyogenes, that is retrieved from a patients throat with a cotton swab. Serological tests, if available, are usually the preferred route of identification, however the tests are costly to develop and the reagents used in the test often require refrigeration. Some serological methods are extremely costly, although when commonly used, such as with the "strep test", they can be inexpensive.
What are serological tests based upon the ability of an antibody to do?
The answer is the following: bind specifically to an antigen

Problem: As of December 2015[update], Barcelona has won 23 La Liga, 27 Copa del Rey, 11 Supercopa de Espana, three Copa Eva Duarte[note 2] and two Copa de la Liga trophies, as well as being the record holder for the latter four competitions. They have also won five UEFA Champions League, a record four UEFA Cup Winners' Cup, a shared record five UEFA Super Cup and a record three FIFA Club World Cup trophies. They also won a record three Inter-Cities Fairs Cup trophies, considered the predecessor to the UEFA Cup-Europa League.
How many UEFA Champions League wins does Barcelona have?
The answer is the following: five

Problem: Though Decca would continue to keep picture budgets lean, it was favored by changing circumstances in the film business, as other studios let their contract actors go in the wake of the 1948 U.S. vs. Paramount Pictures, et al. decision. Leading actors were increasingly free to work where and when they chose, and in 1950 MCA agent Lew Wasserman made a deal with Universal for his client James Stewart that would change the rules of the business. Wasserman's deal gave Stewart a share in the profits of three pictures in lieu of a large salary. When one of those films, Winchester '73, proved to be a hit, the arrangement would become the rule for many future productions at Universal, and eventually at other studios as well.
Who was a notable talent agent circa 1950?
The answer is the following: Lew Wasserman

Problem: All modern birds lie within the crown group Aves (alternately Neornithes), which has two subdivisions: the Palaeognathae, which includes the flightless ratites (such as the ostriches) and the weak-flying tinamous, and the extremely diverse Neognathae, containing all other birds. These two subdivisions are often given the rank of superorder, although Livezey and Zusi assigned them "cohort" rank. Depending on the taxonomic viewpoint, the number of known living bird species varies anywhere from 9,800 to 10,050.
What is another name for Aves?
The answer is the following:
Neornithes