Unit 3 A healthy life language points课时作业

Ⅰ. 阅读理解

(2017·四川邻水实验中学高二月考)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，which was 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.