观察图,人类没有而洋葱叶肉细胞具有的结构是 ( ) ①细胞壁②细胞膜③叶绿体④

题型:选择题

问题:

观察图,人类没有而洋葱叶肉细胞具有的结构是

(  )

①细胞壁 ②细胞膜 ③叶绿体 ④细胞质 ⑤液泡 ⑥细胞核.

A.①②③

B.①③⑤

C.②④⑥

D.①⑤⑥

考点:植物细胞结构和功能动物细胞结构和功能
题型:选择题

人类能创造出“猪八戒”这一并不客观存在的文学形象,恰好说明了()

A.心理是脑的功能

B.心理是对客观现实的反映

C.心理是极其复杂的

D.心理是对客观现实主观能动的反映

E.动物也有心理现象

题型:选择题

在英国,有着一套完整的工程建设标准合同体系,其中()是英国的主要合同体系,主要通用于房屋建筑工程。

A.JCT合同体系

B.ACA合同体系

C.ICE合同体系

D.皇家政府合同体系

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阅读理解

     A primary school teacher who left a class of 25 pupils in tears after she told them Santa Claus did not

exist has been fired. When excited youngsters became rowdy as they talked a- bout Santa, the supply

teacher said out suddenly, "It's your parents who leave out presents on Christmas Day."

     The class of seven-year-olds at Blackshaw Lane Primary School, Royton, Greater Manchester burst in

to tears and told their parents when they arrived home. Mothers and fa- thers then complained about the

incident and were sent a letter by the school saying the teacher, who only worked at the school for one day

last week, has been punished.

     The school has now said it will not hire her again.

     One father said, "My son came home and said that his teacher had told the class that Santa doesn't

exist and it's their mum and dad that put out presents for them. Obviously, they were all talking about

Christmas and being a bit rowdy. She just came straight out with it. "

     "My son was in tears and so was everyone else in the class -- especially as it was so close to

Christmas. I thought it was wrong. He was crazy about it. He's only seven-year-old and it's part of the

magic of Christmas to him. "

     "We told him that she did not believe in Father Christmas because of her religion and he's fine now. "

     "The father described the incident as ' shocking' and believed it was done with malicious intent (恶意地). A lot of parents were angry and complained to the school. The teacher, who was supplied by

Rochdale and Oldham Supply Agency, is still listed and will work with other schools," the agency said.

     However, the head teacher in Angela McCormick refused to comment on the incident.

1. Who felt the angriest about the incident?

A. The teacher who was fired.            

B. The parents whose children cried.

C. The pupils who were in tears.          

D. Santa Claus the teacher talked about.

2. The seven-year-old children cried because of        .

A. something about Santa Claus          

B. the letters by the school

C. their teacher's leaving              

D. the presents left out by the parents

3. We can infer from the passage that       .

A. the teacher was fired and couldn't continue her career in teaching

B. the parents complained about the discipline of the school

C. the little pupils felt disappointed after hearing the news told by the teacher

D. in reality, Santa Claus exists and gives out presents once a year

4. What's the meaning of the underlined word "rowdy"?

A. surprised.      

B. noisy.        

C. discouraged.  

D. annoyed

题型:选择题

公元2000年到来之际,人类忽然发现多少年来对生命的认识将被重新改写。1997年克隆羊的诞生,使人类可以利用生物体上的一个非胚胎细胞复制生命;仅仅两年之后的新发现。将使人类可以利用无生命的物质创造出新的生命来。

世界权威的科学刊物《科学》杂志报道了这个惊人的发现,科学家已经找到了形成生命所需要的基因数量。这个消息犹如一发重磅炸弹,轰动了科学界。人们认识到,这意味着科学界能够利用没有生命的化学物质在实验室中制造出生命来。

美国马里兰州基因组研究所对一种细菌进行层层拆解,一直拆到生命所必需的基因。科学家们发现,构成一个简单生命至少需要265到350个基因,这300个左右的基因是建构生命体最小的分子指令集。该基因研究所的遗传专家克雷格文特尔博士说,这项研究是用生物体全部基因的集合,即基因组 genome),对生命重新定义。

科学界研究的这种细菌生存于人类的生殖器及肺部,是世界上最小的生物体。它不会给人体带来什么疾病,但所含的基因数目少于任何其他已知生物。人类基因数在80000到140000之间,而这种细菌只有480个。克雷格文特尔等人使该细菌中的基因逐个失去活性,如果细菌死亡,说明这一被杀死的基因是该细菌成活所必需的,通过对大量该细菌的测试,他们发现了这种细菌成活所必需的基因。由于这种细菌是最简单的生命形式,因此它所必需的基因数量也就是生命所必需的基因数量。

《科学》杂志还报道说,经过分析发现,这种细菌的必需基因中,有100个基因的功能目前仍不清楚。这些未知但却是必需基因的存在,表明人类尚未了解关于基本生命的每一件事。

对作为研究对象的“一种细菌”的理解,不符合原文意思的一项?()

A.在生物界里,这种细菌是世界上最小的生物体

B.这种细菌存在于人的生殖器和肺部,不会使人产生疾病

C.这种细菌的基因数目少于任何其他已知生物

D.这种细菌的基因数目只有480个,比人类基因数目少166倍多

题型:选择题

在通货膨胀期间,人们的储蓄存款和所有以货币计算偿付的债权的实际价值都会随着物价的上涨而()。

A.增加

B.减少

C.不变

D.增加或减少

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