问题 选择题

鲫鱼不停地将水吞人口内,又从鳃盖后缘流出.流出鳃的水和进入鳃的水相比,水中其溶解的气体成分变化情况是(  )

A.两者所含气体成分多少相同

B.流出的水氧气含量增加,二氧化碳减少

C.流出的水氧气含量减少,二氧化碳增加

D.流出的水氧气含量增加,二氧化碳增加,

答案

鱼的呼吸器官是鳃,水由口进入然后经鳃盖后缘流出,当水流经鳃丝时,水中的溶解氧进入鳃丝的血管中,而二氧化碳由鳃丝排放到水中,二者进行气体交换,所以流出鳃的水和进入鳃的水相比,流出的水中氧气含量减少,二氧化碳增加.

故选:B

解答题
填空题

B The Beatles甲壳虫乐队
The English rock music group The Beatles gave the 1960s its characteristic musical flavor and (1) a profound influence on the course of popular music, equaled by (2) performers. The guitarists John Winston Lennon, James Paul McCartney, and George Harrison; and the drummer Ringo Starr, were all born and (3) in Liverpool. Lennon and McCartney had played together in a group called The Quarrymen. With Harrison, (4) formed their own group, The Silver Beatles, in 1959, and Starr joined them in 1962. As (5) Beatles, they developed a local following in Liverpool clubs, and their first recordings, "Love Me Do" (1962) and "Please Please Me" (1963), quickly made them Britain’s top rock group. Their early music was (6) by the American rock singers Chuck Berry and Elvis Presley, but they infused a hackneyed musical (7) with freshness, vitality, and wit.
The release of "I Want to Hold Your Hand" in 1964 (8) the beginning of the phenomenon known as"Beatlemania" in the United States. The Beatle’s first US (9) aroused a universal mob adulation. Their concerts were scenes of mass worship, and their records sold (10) the millions. Their first film, the innovative A Hard Day’s Night(1964), was received enthusiastically (11) a wide audience that included many who had never before listened to rock music.
Composing their own (12) , The Beatles established the precedent for other rock groups to play their own music.Experimenting with (13) musical forms, they produced an extraordinary (14) of songs: the childishly simple "Yellow Submarine" ; the bitter social commentary of "Eleanor Rigby" ; parodies of earlier pop styles; new electronic sounds; and compositions that were scored for cellos, violins, trumpets, and sitars, as well as for conventional guitars and drums. The (15) disbanded in 1970, after the release of their final album, Let It Be, and during the 1970s (16) individual careers, On dec.8, 1980, John Lennon (17) fatally shot outside his Manhattan apartment by Mark Chapman, a 25-year-old former mental (18) who, earlier that same day, had asked Lennon for his (19) . Lennon’s murder was universally (20) with an intensity of feeling usually inspired only by political and spiritual leaders.