人、噬菌体、禽流感病毒中参与构成核酸的碱基种类数分别是 (   

人、噬菌体、禽流感病毒中参与构成核酸的碱基种类数分别是 (     )

   A445      B544     C454     D545

答案

B

相关题目

阅读下面文字,完成下列小题 齐白石授徒时有一句名言:“
阅读下面文字,完成下列小题 齐白石授徒时有一句名言:“学我者生,似我者死。”李苦禅谨记老师的这句话,因此他学的是老师独到的艺术匠心,而
(08广安)在一个重2N,底面积为0.01扩的容器里装8N的水,容
(08广安)在一个重2N,底面积为0.01扩的容器里装8N的水,容器中水的深度为0.05m。,把它放在水平桌面上,如图12所示(g=1ON/kg)。求:(1)水对容器底
The students were all tired, but ___ of them stopped to have a rest.A.noneB
The students were all tired, but ___ of them stopped to have a rest.A.noneB.eachC.eitherD.neither
He lay in bed, with his eyes ______ up at the ceiling and his fingers ______. A.
He lay in bed, with his eyes ______ up at the ceiling and his fingers ______. A. looked; crossing    B. looking; crossing    C. looking; crossed   D. looked; crossed
化学与环境密切相关.下列有关说法错误的是( ) A.CO、NO
化学与环境密切相关.下列有关说法错误的是( ) A.CO、NO能与人体的血红蛋白结合,使人中毒 B.CaO能与SO2反应,可作工业废气的脱硫剂 C.光化学
函数y=log3(x2-2x)的单调减区间是________.
函数y=log3(x2-2x)的单调减区间是________.
 Kitty is a good dancer and she_______ dancing after school every day. A. need
 Kitty is a good dancer and she_______ dancing after school every day. A. needs           B. practices         C. makes          D. dreams
以下面给出的文字为开头,以路为中心,分别写一段话。(
以下面给出的文字为开头,以路为中心,分别写一段话。(每段不少于50各字) ⑴北京的路平直而宽阔□□□□□□□□□□□□□□□□□□□□□

最新题目