【单选题】人体正常的体细胞染色体数为2n,次级精母细胞的染色体数为( )
【单选题】Bill likes playing ______ pingpong, but he doesn't like playing ______ guitar. [ ]
【单选题】下列关于细胞内元素和化合物叙述正确的是()
B.
DNA分子的基本骨架和细胞膜的基本骨架都含有C,H,O,N,P
C.
人体缺乏I元素,血液中TRH、TSH和TH均减少
D.
细胞的统一性还包括都以DNA分子为遗传物质,mRNA密码子通用等等
【单选题】He is learning to playing _______ guitar.
【单选题】Linda likes playing ______ sports, but she dislikes playing ______ guitar.
【单选题】Lily likes playing _______ guitar.
【单选题】She likes playing _____ guitar while her brother is fond of playing _____ football.