Tiêu đề Unit 6.docx ✅

1. Gorilla and chimpanzee populations in Central Africa continue to decline due to _____________, habitat loss and disease. 2. To ensure the _____________ of the world's animals, we must learn how to keep 'sustainable populations' alive for the animals to _____________ on their own. 3. We now realise that it is important to maintain the planet's _____________, which is the richness of animal and plant life. 4. A _____________ is any natural region where wildlife lives undisturbed, for example, forests, ponds, marshes or deserts. 5. Take _____________ actions in your own community. 6. Officials said there were no _____________ of the plane crash. IV) -Fill in each blank with the suitable word from the root word provided. 1. survive (v) A. Many of our crop plants rely on some insects to produce seeds, and would not _____________ without them. B. By protecting the habitats, we ensure the _____________ of gorillas and the other species. C. The government is sending help to the _____________ of the earthquake. 2. conserve (v) A. To save mountain gorillas, we must _____________ their habitat. B. There are _____________ organisations which try to make people aware of the problems facing wild animals. C. ____________ are calling for additional measures with a focus on more effective management of the habitat. 3. danger (n) A. There are many different organizations working to protect and conserve _____________ species and their habitats. B. The destruction of wildlife habitats is a major cause of species _____________. C. Floods and droughts are both _____________ to humans and crops. 4. extinct (adj) A. The dodo very quickly declined in numbers, and it was _____________ by 1681. B. People all over the world are working to help save endangered animals from ___________. C. The fireman could not _____________ the flames. 5. vulnerable (adj) A. The impacts of biodiversity loss include fewer new medicines, greater _____________ to natural disasters and greater effects from global warming. B. Komodo dragons are listed as _____________ because human activity and natural disasters reduced their number significantly in the past century. C. His condition left him _____________ exposed to the slightest cold or cough. V. Choose the correct verb form to complete the sentences. 1. I think I _______ my door key. I can’t find it anywhere. A. will have lost B. am losing C. have lost D. will lose 2. Mr. Edwards _______ history for 35 years, and is retiring soon. A. teaches B. will have taught C. taught D. has been teaching 3. The number of working women in our country _______ from 49% in 1980 to nearly 65% nowadays. A. has been increasing B. has increased C. is increasing D. will have increased 4. By the time you come back, I _______ my assignments.

Scientists have proposed reviving an extinct species using two possible methods. In the first method, sex cells (sperm or eggs) are obtained from the extinct animal and are used to fertilize sex cells of a closely related living relative in a laboratory. For example, sperm from a wooly mammoth could be used to fertilize an egg from a modern-day elephant. The fertilized egg would then be placed in the live female elephant where it would live and grow until it is ready to be born. The second method involves a type of cloning. In cloning, the DNA of one individual replaces the DNA of another. In the woolly mammoth example, scientists could inject DNA from a mammoth into an egg cell from an elephant. The cloned egg would then be placed into a living elephant and allowed to develop in the same way as a fertilized egg. But some scientists believe species revival will never happen because both methods are problematic. One of the major challenges is how to obtain enough high-quality DNA from an extinct species to conduct an experiment. Scientists have been able to clone only a few species of animals, and most cloned animals don’t live very long. And there is a final, ethical consideration. Even if we learn to reproduce an example of an extinct species, that individual could never have a normal life. Its natural environment is most likely gone and it would have no parents to show it how to behave as a member of its species. So the animal would remain a curiosity and probably live out its life in a zoo. Only time will tell if scientists manage to carry out their ambitious plans. Even if they manage to overcome the scientific problems, they may face opposition from society. Some even feel it might be more worthwhile for us to focus our efforts on conservation and take care of existing species, so they don’t also go the way of the wooly mammoth. Task 1: Read the text, and identify whether the statements are true (T), or false (F). T F 1. Studying extinct species can help us understand the past.   2. The moa is known for the dark stripes down its back.   3. The bucardo died out before the mammoth did.   4. Both methods require the extinct species to develop from an egg.   5. Scientists have successfully managed to preserve mammoth DNA.   6. People may not want to see extinct species revived.   7. Scientists have been able to clone an extinct species.   8. Most cloned species have long life expectancy.   Task 2: Read the passage again, and choose the correct answer A, B, C or D for each question. 1. Which statement is true regarding the number of species on the Earth? A. At one point, there used to be over a billion species living on the Earth. B. There are more extinct species than there are living species. C. About 20 species of animals are going extinct every day. D. Throughout the Earth's history, more than one billion species of animals have existed. 2. What does the last sentence of the second paragraph “So it seems somehow fitting that we are now thinking of reviving them ” mean? A. These species deserve to be revived because they died of unnatural causes. B. Only humans have the intelligence and ability to revive these extinct species. C. Since these species lived at the same time as humans, we know how to revive them. D. Since humans contributed to their extinction, humans should also be responsible for their revival. 3. Both methods of reviving an extinct species require _______. A. the DNA of the extinct species B. the sperm of the extinct species C. a living species that is closely related to the extinct species D. the cloned egg cells placed into a living species