2020年高考英语 艺术生 强化训练课时作业40 天 临阵磨枪(11)

课时作业(九)

Ⅰ.阅读理解

[2019·山东菏泽一模] It's easy to think that the globe's vast oceans would be effective barriers to the movement of land animals.An elephant can't swim across the Pacific，after all.But it turns out that plenty of plants and animals have unintentionally floated across oceans from one continent to another.Now comes evidence that tiny trapdoor spiders(活板门蛛) made such a journey millions of years ago.

Moggridgea rainbowi spiders can be found on Kangaroo Island，which sits off the south coast of Australia.“These spiders build a silk-lined burrow(洞穴) in the ground，”noted Sophie Harrison，a biologist in Australia.The burrow and the trapdoor provide these spiders with shelter and protection.They also offer them an out-of-sight spot from which they can wait for approaching prey(猎物) .

There is evidence，though，that the ancestors of them might have traveled millions of meters to get to Australia from Africa.That isn't as unlikely as it might at first seem.Australia used to be connected to other continents，long ago，as part of a supercontinent called Gondwana.And humans have been known to transport species(物种) all over the planet.But there's a third option.The spiders might have rafted(乘筏) long distances across the sea.

To figure out which story was most likely true，Harrison and her colleagues looked at the spider's genes.They looked at the genes in seven Moggridgea rainbowi spiders from Kangaroo Island，and five species of Moggridgea rainbowi spiders from South Africa.The Australian and African spiders split off from a common ancestor some 2 million to 16 million years ago，the genes showed.

If a large swatch(块) of land washes into the sea，filled with arachnids(蛛形纲动物)，the spiders may be able to hide themselves throughout the journey.Plus，they can “hold their breath” and survive on stored oxygen during periods of temporary flooding，the researchers note.

1．What is the common belief about land animals according to the text?

A．They are sensitive to natural disasters.

B．They are unlikely to move across oceans.

C．They can't make a long ocean voyage.

D．They float across oceans accidentally.

2．What does the underlined word “them” in Paragraph 3 refer to?

A．The biologists. B．The Australians.

C．The spiders. D．The prey.

3．How did the researchers conclude Australian and African spiders are from a common ancestor?

A．By comparing their genes.

B．By observing their living habits.

C．By making changes to their genes.

D．By studying their physical characteristics.

4．What could be the best title for the text?

A．These Spiders Traveled Globally to Hide Themselves

B．These Spiders Became More Adaptive When Traveling

C．These Spiders Crossed an Ocean to Australia for

Survival

D．These Spiders Crossed an Ocean to Become Australian

Spiders

[解题导语]本文是一篇说明文。研究表明：澳大利亚活板门蛛是几百万年前从非洲漂洋过海迁徙到澳大利亚的。

1．B解析：细节理解题。本题题干意为：根据本文，人们对陆地动物的普遍观点是什么？根据第一段第一句(人们会轻易地认为地球上的大洋可以有效阻隔陆地动物的迁徙)可知答案为B项(它们不可能跨越海洋)。A项(它们对自然灾害很敏感)，C项(它们不能长距离航海)，D项(它们偶然漂过了海洋)在文中均未提及，故排除。

2．C解析：代词指代题。本题题干意为：第三段中画线词“them”指的是什