Question

Imagine putting a seed in a freezer,waiting 30,000 years,and then taking the seed out and planting it. Do you think a flower would grow?

Amazingly, scientists have just managed to do something very similar. They found the fruit of an ancient plant that had been frozen underground in Siberia—a region covering central and eastern Russia—for about 31,800 years. Using pieces of the fruit,the scientists grew plants in a lab. The new blooms have delicate white petals. They are also the oldest flowering plants that researchers have ever revived from a deep freeze.

“This is like regenerating a dinosaur from tissues of an ancient egg,’’said Jane Shen-Miller,a biologist of University of California,Los Angeles.

The plant has a long history. Back when mammoths and woolly rhinoceroses walked on the land, an Arctic ground squirrel buried seeds and fruits in an underground chamber near the Kolyma River in northeastern Siberia. The ground became pennafrost, a layer of soil that stays frozen for a long time.

Recently, Russian scientists dug out the old squirrel hole and found the plant remains 38 meters below the surface. Back at the lab, the team fed nutrients to tissue from three of the fruits to grow shoots. Then the scientists transferred the shoots to pots filled with soil. The plants produced seeds that could be used to grow even more of them.

It’s important for scientists to know that plant tissues can still be revived after being frozen for a long time. That’s because many researchers are trying to preserve the seeds of modem plants by freezing them and then storing them in giant lockers at various spots around the globe. One such endeavor,an underground facility in Norway,is called the Svalbard Global Seed Vault. It stores hundreds of thousands of frozen seeds. If a plant ever goes extinct, scientists could bring it back by taking its seeds from the Svalbard or other storage lockers.

“No one knows how long they are able to live for,but freezing is basically the format for many plant conservation attempts nowadays,’’Jane Shen-Miller said. It’s a good thing that at least some plants are tough enough to survive in the experience.

1.Which of the following was NOT used to recreate the ancient plant?

A. Modem nutrients.

B. Parts of the fruits.

C. Its frozen seeds.

D. Plant pots with soil.

2.Why are scientists interested in this discovery?

A. It helps them learn how plant life has changed in the past 30,000 years.

B. It can help guide future efforts to protect endangered plants’ life.

C. It can provide directions for where to look for other ancient plants.

D. It proves that all plant life can survive for thousands of years when frozen.

3.The underlined word "they", in the final paragraph refers to             .

A. plants

B. seeds

C. scientists

D. storage lockers

4.The purpose of the passage is to            .

A. discuss a plant conservation effort

B. introduce some ancient plants

C. outline some causes of global warming

D. describe a scientific research project

Answer

1. C

2. B

3. B

4. D

【解析】

本文是一篇科普说明文，介绍了科学家研究利用冷冻的方法再生古代植物，这个研究有助于保护濒危植物。

1.细节理解题。根据第二段中的“They found the fruit of an ancient plant that had been frozen underground in Siberia—a region covering central and eastern Russia—for about 31,800 years. Using pieces of the fruit,the scientists grew plants in a lab.”可知，科学家用在西伯利亚冷冻了大约31,800年的古代植物碎片种植植物，根据第五段中的“Back at the lab, the team fed nutrients to tissue from three of the fruits to grow shoots. ”可知，研究人员给果实的组织提供营养，让它们长出嫩芽，根据第五段中的“Then the scientists transferred the shoots to pots filled with soil.”可知，科学家把幼苗移到装满土壤的花盆里，而文章没有提到用冰冻的种子再生古代指物，故C项正确。

2.细节理解题。根据倒数第二段中的“If a plant ever goes extinct, scientists could bring it back by taking its seeds from the Svalbard or other storage lockers.”可知，如果一种植物灭绝了，科学家可以取出储藏柜中的种子，让它复活，也就是这个研究有助于保护濒危植物，故B项正确。

3.词义猜测题。根据上文中的“If a plant ever goes extinct, scientists could bring it back by taking its seeds from the Svalbard or other storage lockers.”可知，如果一种植物灭绝了，科学家可以取出储藏柜中的种子，让它复活，此处是说没有人知道这些种子能活多久，但是冷冻基本是当今植物保护尝试的形式，由此可知，they指代的就是前面提到的种子，故B项正确。

4.文章意图题。通读全文，特别是根据第一段“Imagine putting a seed in a freezer, waiting 30,000 years, and then taking the seed out and planting it. Do you think a flower would grow?”及第二段中的“Amazingly, scientists have just managed to do something very similar.”可知，本文介绍了科学家研究利用冷冻的方法再生古代植物，这个研究有助于保护濒危植物，因此这篇文章的目的就是描述这个科研项目，故D项正确。