【正文】
.c. a storybook. d. a novel.[分析] 主旨題型。見本文主旨句,第二段第一句:the study ofisolated roots has provided an understanding of therelationship between shoots and roots in intactplants.(第一段談的是the study of isolated roots。第二段談的是the relationship between shoots and roots):因此選項(xiàng)a應(yīng)為答案。[分析] 細(xì)節(jié)題型。見第一段第一句:about fifty years ago,plant physiologists set out to grow roots bythemselves in solutions in laboratory flasks,這里指plant physiologists自己培育根用作物。因此themselves在此應(yīng)為正確選項(xiàng)。[分析] 細(xì)節(jié)題型。見第一段第三句:they required sugar and the usual minerals and 。[分析] 細(xì)節(jié)題型。見第一段第六句:roots are capable of making their own proteins and other 。[分析] 推斷題型。第一段提到(塊)根需要sugar and the usual minerals and vitamins,但不需要 organic nitrogenpounds,因(塊)根可自造所需的蛋白質(zhì)和其它organic pounds。這里反復(fù)提到的organicpounds應(yīng)包括the high energy pound atp(見第一段倒數(shù)第二句)。因此可推斷出選項(xiàng)c(一種化合物)為答案。