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英语口语科学60秒

栏目: 校园 / 发布于: / 人气:5.77K

One of the ways the meek may inherit the Earth is by cheating death. The microscopic animal known as a water bear can spring back to life — even after being exposed to the vacuum and [ 1 ] radiation of space for more than a week.

英语口语科学60秒

At least that's what scientists found out when they sent the 1.5-millimeter-long creature into orbit in 2007. Nor are water bears alone. Some insect larvae, rotifers, nematodes and even brine shrimp can be seemingly dead for years, only to be revived by adding water. Sea monkeys [ 2 ].

Then there are the extremophiles. Deinococcus radiodurans may be the toughest. When high levels of ionizing radiation [ 3 ] this microorganism’s very DNA—killing it for all intents and purposes—its genetic code repairs itself and the organism comes back to life within hours. These hardy microbes would likely survive any apocalypse we throw at them.

Then there are the higher life forms. With hydrogen sulfide gas, mice can be put into a state of [ 4 ] animation that allows them to survive without breathing for up to six hours. This mammalian proof-of-concept offers hope that the technique could someday work with humans. Of course, the big problem with that experiment is finding volunteers.