【单选题】I n a n econom y wher e ne t export s ar e zero , i f savin g rise s i n som e period , the n i n tha t period
A.
consumptio n an d investmen t fall.
B.
consumptio n fall s an d investmen t rises.
C.
consumptio n rise s an d investmen t falls.
D.
consumptio n rise s an d investmen t rise s.
【简答题】1958年美国科学家将胡萝卜韧皮部的细胞培养产生完整植株,如下图所示,请回答: (1)科学家所用的胡萝卜韧皮部的细胞,在正常生物体内是否能够进行有丝分裂?说明原因。_________。 (2)韧皮部细胞通过_______和_______,形成许多植株的特点是________。 (3)此实验证明了高度分化的植物细胞仍有发育成完整植株的能力,即具有________,高度分化的细胞具有此特性是由于___...
【简答题】上皮组织化生举例 :____,____。
【单选题】Movie Time book 2 unit 6_1.WMV 2. What did Bob worry about?
A.
He worried about his life after being fired.
B.
He worried that his children would not work hard in their studies.
C.
He worried about the lack of chance to cook.
D.
He worried that he couldn’t be an athlete.
【单选题】主动运输与入胞作用的共同点是______。
【判断题】“生食类食品”一般特指生食水产品,尽量不要生食淡水水产品。()
【多选题】问答式的讲解方式主要有哪几种表现形式?( )
【单选题】You need to keep an eye out during your speech for audience __________.