It would be unfair to clone any extinct anima...

It would be unfair to clone any extinct animals ________ they were to live in a zoo.

高二英语单项填空简单题查看答案及解析

It never occurred to humans until the mid-1990s          some animals can be cloned.

A. where    B. that             C. when         D. what

高二英语单项填空中等难度题查看答案及解析

It never occurred to humans until the mid-1990s ______ some animals can be cloned.

A. where                B. that                 C. when                 D. what

高二英语单项填空中等难度题查看答案及解析

An extinct mountain goat that was once common in the Pyrenees became the first animal to be brought back from extinction. Researchers used frozen DNA to produce a clone, but the newborn kid died within minutes of birth due to breathing difficulties.

The Pyrenean ibex is a type of mountain goat，which is believed to have died out completely in 2000. Before the death of the last known individual（a13-year-old female known as Celia）, biologists took cells from her skin and ears. An earlier cloning attempt to use the skin cells failed. But the latest attempt involved the creation of 439 cloned embryos. Of these cloned embryos, 57 were put into the female domestic goats, but only one goat gave birth and the newborn cloned kid died after seven minutes as a result of lung disease.

Researchers say that other cloned animals, including sheep, have been born with similar lung disease, but they say that overall the experiment was a major step forward in the effort to bring the ibex back to its mountain home. The leading researcher Jose Folch says, “the cloned kid was genetically like the ibex；in species such as the ibex，cloning is the only possibility to avoid its complete disappearance.”

The failure to produce a living clone from DNA that was frozen only a decade ago shows the difficulty researchers would face in trying to bring back species that have been extinct（灭绝的） for decades or centuries. Researchers have had the idea of bringing back the Tasmanian tiger, which went extinct in 1936. There are, however, other species that have been seriously suggested for cloning，such as the giant panda, the African bongo antelope, the Sumatran tiger and the pygmy hippo. Supporters believe cloning provides hope of keeping these endangered animals alive before they die out．

1.What do we know about the cloned ibex?

A. It died of lung disease.

B. It was the first cloned animal in the world.

C. It lived for thirteen years.

D. It was born in 2000.

2.Jose Foleh would agree that cloning　　　　 ．

A. is not suitable and should be banned.

B. requires immediate attention.

C. should be carried out cautiously.

D. may help prevent animal extinction.

3.We can conclude from the passage that　　　　 ．

A. cloning has developed quickly in developed countries.

B. no more animals will die out in the future.

C. cloning makes it possible to preserve endangered species.

D. cloning seldom results in physical problems for animals.

4.What’s the best title for this passage?

A、Great advancement in cloning goats.

B、Difficulties in saving extinct animals.

C、Public concerns about cloning.

D、Cloning brought back an extinct species for a while.

高二英语阅读理解困难题查看答案及解析

All efforts of cloning an animal will be ________ if there is not enough diversity in the group to overcome illness.

高二英语单项填空中等难度题查看答案及解析

A new study shows the world’s fastest land animal could be running towards extinction.

The Zoological Society of London (ZSL), Panthera, and Wildlife Conservation Society (WCS) led the study. It estimates that only 7,100 cheetahs（猎豹）remain worldwide, mainly found in Africa. But according to the study, cheetahs have been forced out of 91% of their native range. Cheetahs found in Asia are among the hardest hit. Fewer than 50 are left in a small part of Iran.

Many factors are to blame for the decline in cheetah numbers, including habitat loss and the illegal trade. Prey（猎物）loss is also a problem. Humans cause it by overhunting animals that cheetahs prey on. Cheetahs are carnivores and prey mainly on smaller mammals, for example gazelles.

Because cheetahs usually roam over large areas in search of food, 77% of their habitat remains outside of government-protected areas. This means cheetahs are in constant danger of hunters and traders. In Zimbabwe, Africa, alone, the cheetah population has dropped from 1,200 to only about 170 in 16 years. This decline represents a loss of 85% of the country’s cheetahs.

Dr. Kim Young—Overton, Panthera’s Cheetah Program Director, thinks protected habitats alone are not enough to save cheetahs. Cheetahs in reserves also face dangers such as loss of prey and illegal trade.

Dr. Sarah Durant, the study’s lead author, believes that the information it contains will lead to a better understanding of cheetahs as well as a better approach to helping them survive. Durant says local and national officials must team up in order to save cheetahs. But first, the International Union for Conservation of Nature must classify the animals as endangered. Currently, cheetahs are classified as weak on the IUCN’s Red List of Threatened Species. The change would focus more attention on cheetahs and help protect them for extinction. After all, in the fight to save cheetahs, it's a race against time.

1.What is the present situation of cheetahs according to the study?

A. They are in danger.

B. They live freely worldwide.

C. They are protected well in Africa.

D. They mainly live in their native range.

2.What does the underlined word “carnivores” refer to?

A. Animals kept at home.

B. Animals living in zoos.

C. Animals feeding on meat.

D. Animals killed in the wild.

3.What results in the decline of the cheetah population according to the text?

A. The loss of their reserves.

B. Their appearance in unpreserved areas.

C. The decreasing government protection.

D. Their increasing natural enemies.

4.What does Dr. Sarah Durant think of the study of cheetahs?

A. It shows ways of wildlife protection.

B. It implies people’s role in saving animals.

C. It stresses the importance of cheetahs in our life.

D. It informs people of cheetahs’ existing state.

高二英语阅读理解中等难度题查看答案及解析

It hasn’t been ______ that food from cloned animals is really safe for humans to eat.

A. confirmed　　　　　　 B. considered

C. turned out　　　　　 D. proved

高二英语单项填空中等难度题查看答案及解析

As I understand, if scientists produced a human clone, there would be a great risk of it having a disease. Nobody seems to understand the ageing process of a clone. It would be terrible if a baby was the age of its parent at 31. Its cells would grow old fast and it would die young.32 until the technique is perfectly safe, it should be 33.

I'd love to have a clone of 34. I often wish I had a twin sister, someone who 35 me in everything. So why not a clone? Well, the idea 36 be fun but I'm not sure if it would be 37. I think we would be playing with fire if we let scientists go ahead with 38 cloning. There are so many 39

involved that all research in this area should be strictly controlled.

There are so many arguments 40 cloning that it is difficult to get anyone to consider the possible benefits. I am 41 that it is a technique which could be beneficial. The most obvious use would be for childless 42. They would be able to have babies with their own genetic material. I don't see what's wrong with that.

Imagine a child 43 up knowing that his or her mother is really a sister or a brother. The emotional 44 on the child would be 45. Or a child who was cloned from a dead brother or sister. What kind of emotional pressure would they feel, knowing they were made as a replacement for another? The whole idea

46 me!

It's all very good to ban human cloning but scientists should be allowed to 47

research. If they don't, we may 48 important benefits for our society, such as producing body organs. A clone is an 49 copy of a person with the same gene. Therefore, it is the 50 donor for an organ(器官) transplant.

高二英语完型填空困难题查看答案及解析

With only about 1,000 pandas left in the world, China is desperately trying to clone (克隆) the animal and save the endangered species (物种). That’s a move similar to what a Texas A & M University researchers have been undertaking for the past five years in a project called “Noah’s Ark”.

Noah’s Ark is aimed at collecting eggs, embryos(胚胎), semen and DNA of endangered animals and storing them in liquid nitrogen. If certain species should become extinct, Dr. Duane Kraemer, a professor in Texas A& M’s College of Veterinary Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.

It is estimated that as many as 2,000 species of mammals, birds reptiles will become extinct in over 100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.

This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.

The entire procedure could take from three to five years to complete.

“The nuclear transfer (核子移植) of one species to another is not easy, and the lack of available (capable of being used) panda eggs could be a major problem,” Kraemer believes. “They will probably have to do several hundred transfers to result in one pregnancy (having a baby). It takes a long time and ifs difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort, adds Kraemer, who is one of the leaders of the Project at Texas A& M, the first-ever attempt at cloning a dog.

“They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly appreciate their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed.”

1.The aim of “Noah’s Ark” project is to ________.

A. make efforts to clone the endangered pandas

B. save endangered animals from dying out

C. collect DNA of endangered animals to study

D. transfer the nuclear of one animal to another

2.According to Professor Kraemer, the major problem in cloning pandas would be the lack of ________.

A. available panda eggs　　 B. host animals

C. qualified researchers　　 D. enough money

3.The best title for the passage may be ________.

A. China’s Success in Pandas Cloning

B. The First Cloned Panda in the World

C. Exploring the Possibility to Clone Pandas

D. China —the Native Place of Pandas Forever

4.From the passage we know that ________.

A. Kraemer and his team have succeeded in cloning a dog

B. scientists try to implant a panda’s egg into a rabbit

C. Kraemer will work with Chinese scientists in clone researches

D. about two thousand of species will probably die out in a century

高二英语阅读理解困难题查看答案及解析

With only about 1,000 pandas left in the world, China is desperately trying to clone (克隆) the animal and save the endangered species(物种).That's a move similar to what a Texas A&M University researchers have been undertaking for the past five years in a project called “Noah's Ark”.

Noah's Ark is aimed at collecting eggs, embryos(胚胎)，semen and DNA of endangered animals and storing them in liquid nitrogen（氮）. If certain species should become extinct, Dr.Duane Kraemar, a professor in Texas A&M University Medicine, says there would be enough of the basic building blocks to reintroduce the species in the future.

It is estimated that as many as 2,000 species of mammals, birds reptiles will become extinct in over 100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.

This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.

The entire procedure could take from three to five years to complete.

“The nuclear transfer(核子移植) of one species to another is not easy, and the lack of available(capable of being used) panda eggs could be a major problem，”Kraemer believes. “They will probably have to do several hundred transfers to result in one pregnancy (having a baby). It takes a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort,” adds Kraemer, who is one of the leaders of the Project at Texas A & M, the first–ever attempt at cloning a dog.

“They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly appreciate their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed.”

1.The aim of “Noah’s Ark” project is to________.

A. make efforts to clone the endangered pandas

B. save endangered animals from dying out

C. collect DNA of endangered animals to study

D. transfer the nuclear of one animal to another

2.The underlined word groundbreaking can be interpreted as __________.

A. especially new　　 B. pioneering

C. damaging　　 　　　 　 D. trouble- making

3.The best title for the passage may be ______.

A. China’s Success in Panda Cloning

B. The First Cloned Panda in the World

C. Exploring the Possibility to Clone Pandas

D. China---the Native Place of Pandas Forever

4.From the passage we know that _______.

A. Kraemer and his team have succeeded in cloning a dog

B. scientists try to implant a panda’s egg into a rabbit

C. Kraemer will work with Chinese scientists in clone researches

D. about two thousand species will probably die out in a century

高二英语阅读理解中等难度题查看答案及解析