问题 选择题

下列有关细胞分裂分化生长叙述不正确的是(    )

A.细胞分裂产生的新细胞与原细胞的染色体数目一样多

B.癌细胞是一种高度分化的细胞,能不断进行分裂

C.细胞生长使得细胞的体积不断增大

D.造血干细胞经过诱导可以形成多种血细胞从而治疗相关疾病,依据的是细胞分化原理

答案

答案:B

题目分析:生物体从小长大,是与细胞的生长、分裂和分化分不开的.细胞的生长使细胞的体积增大,细胞分裂使细胞数目增多.新产生的细胞体积都很小,通过不断从周围环境吸收营养物质并且转变成组成自身的物质,体积会由小变大,这就是细胞的生长.但细胞不能无限制的长大长到一定大小会进行分裂.细胞的分裂就是一个细胞分裂成两个细胞.细胞分裂的过程是,细胞核先由一个分成两个,随后细胞质分成两份,每份各含有一个细胞核.最后,在原来的细胞中央,形成新的细胞膜,植物细胞还形成新的细胞壁.于是,一个细胞就分裂成为两个细胞.癌细胞是一种发生了基因突变的细胞,它的分裂导致病变的发生。

因此,癌细胞是一种高度分化的细胞,能不断进行分裂是错误的.故选:B

单项选择题

The Southdale shopping centre in Minnesota has an atrium, a food court, fountains and acres of parking. Its shops include a Dairy Queen, a Victoria’s Secret and a purveyor of comic T-shirts. It may not seem like a landmark, as important to architectural history as the Louvre or New York’s Woolworth Building. But it is. "oh, my god!" chimes a group of teenage girls, on learning that they are standing in the world’s first true shopping mall. "That is the coolest thing anybody has said to us all day. "

In the past half century Southdale and its many imitators have transformed shopping habits, urban economies and teenage speech. America now has some 1,100 enclosed shopping malls, according to the International Council of Shopping Centres. Clones have appeared from Chennai to Martinique. Yet the mall’s story is far from triumphal. Invented by a European socialist who hated cars and came to deride his own creation, it has a murky future. While malls continue to multiply outside America, they are gradually dying in the country that pioneered them.

Southdale’s creator arrived in America as a refugee from Nazi-occupied Vienna. Victor Gruen was a Jewish bohemian who began to design shops for fellow immigrants in New York after failing in cabaret theatre. His work was admired partly for its uncluttered, modernist look, which seemed revolutionary in 1930s America. But Gruen’s secret was the way he used arcades and eye-level display cases to lure customers into stores almost against their will. As a critic complained, his shops were like mousetraps. A few years later the same would be said of his shopping malls.

By the 1940s department stores were already moving to the suburbs. Some had begun to build adjacent strips of shops, which they filled with boutiques in an attempt to re-create urban shopping districts. In 1947 a shopping centre opened in Los Angeles featuring two department stores, a cluster of small shops and a large car park. It was, in effect, an outdoor shopping mall. Fine for balmy southern California, perhaps, but not for Minnesota’s harsh climate. Commissioned to build a shopping centre at Southdale in 1956, Gruen threw a roof over the structure and installed an air-conditioning system to keep the temperature at 75°F (24℃)—which a contemporary press release called "Eternal Spring". The mall was born.

Gruen got an extraordinary number of things right first time. He built a sloping road around the perimeter of the mall, so that half of the shoppers entered on the ground floor and half on the first floor-something that became a standard feature of malls. Southdale’s balconies were low, so that shoppers could see the shops on the floor above or below them. The car park had animal signs to help shoppers remember the way back to their vehicles. It was as though Orville and Wilbur Wright had not just discovered powered flight but had built a plane with tray tables and a duty-free service.

According to the text, which of the following is TRUE()

A. Southdale will be closed soon

B. Shopping malls are flourishing all over the world

C. After long time of prosperity, shopping malls in US is gradually declining

D. Shopping mall is an American creation

填空题