小明吃饭时发现红色苋菜和米饭混合后，米饭被染成红色。这种红色色素主要来自苋菜细胞的
A．细胞膜
B．细胞质
C．液泡
D．细胞核
答案：C
题目分析：A、细胞膜，紧贴细胞壁内侧，非常薄，在光学显微镜下不容易看清楚，起保护作用并控制物质进出的作用．
B、细胞质是细胞膜以内，细胞核以外的结构，活细胞的细胞质具有流动性，从而加速细胞内、外的物质交换．
C、液泡中含有细胞液，有各种味道的物质以及营养物质和各种色素等，各种蔬果汁中含各种有味道的物质、色素以及丰富的营养物质，就是来自于细胞中液泡的细胞液．
D、细胞核内含遗传物质，对生物的遗传具有重要的意义．
Li Yang’s brother is a 1 . He works in a bank. One day, he was driving two bags full of 2 important. But he and his truck were lost. The police looked for three hours, then they found Li Yang’s 3 and his truck. His 4 were tied（捆绑）behind his back. The bad man put something round his 5 so that he could not shout. The police climbed into the back of the truck and freed Li Yang’s brother. They asked him what happened.“They asked me to stop soon 6 I left the bank,” his brother said. “Six men stopped me and made me 7 to the river. “If you shout,” one of them said, “we will cut you into pieces.” When I got to the river, they tied 8 up. Then they threw me to the back of the truck. I sat on one of the 9 quietly. They didn’t see the bag, and took the other one.” “How much money was there in the bag? ”a policeman asked. “There was not any 10 in it at all,” Li Yang′s brother laughed. “Only some letters, the money is in this one. I was sitting on it. What a brave and clever man he is!
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