题干

下面对高等动物通过减数分裂形成的雌、雄配子以及受精作用的描述,其中正确的是(    )

A:每个卵细胞继承了初级卵母细胞 14 的细胞质

B:受精时精子与卵细胞相互识别与细胞膜上的糖蛋白有关

C:受精卵中的遗传物质父方和母方各提供一半

D:雌、雄配子彼此结合的机会相等,因为它们的数量相等

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B

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    Imagine that you're the creator and show runner of the newest comedy show on television. Only it isn't so popular yet, and your live Studio audience isn't giving you the big laughs the show deserves. Do you film the show all over again, hoping that this time the audience will laugh? Or is there another option for making a joke sound funnier than it was received?

    Sweeten(改善) the sound by adding a laugh track! “Sweetening,” or the addition of sound effects such as laughs, screams, and other audience-produced noises to the audio track of a TV show, has been used since the 1940s to produce the appearance, or rather the sound, of an engaged and entertained response to a show's comedy. Laugh tracks came into existence as not only a solution, and sometimes replacement, for an unengaged live audience but also as a way to engage an at-home audience into a more-traditional, public, and theaterlike experience. Adding a laugh track to a television show makes the viewers at home feel much less like they're sitting on a couch staring at the television screen and much more like they're in a room full of laughing happy people to varying degrees of success.

    Though the art of sweetening has risen and fallen in popularity over the past 60 years, credit for its creation and continued use is owed to laugh-track pioneer and sound engineer Charles Douglass. Douglass was the first to develop, in 1953, a machine for producing “canned laughter”, accessible at the push of a button or pull of a lever (操纵杆). Despite being artificial, sensibly edited laugh tracks are found by television studios to bring about a positive audience response, as their use is usually accompanied by higher ratings and increased audience memory. Though some television audiences may disagree with the value of the laugh track, the cheerful and repetitive sound holds a permanent place in the history and future of television comedy.