课程咨询
托福培训

扫码免费领资料

内含托福全科备考资料

更有免费水平测试及备考规划

托福培训

扫码关注掌握一手留学资讯

回复XDF免费水平测试

托福听力练习-科学美国人60秒:紫外线致皮肤癌

2017-04-04 10:14:00来源:科学美国人60秒

点击查看>>科学美国人60秒音频:紫外线致皮肤癌

  科学美国人60秒听力练习:紫外线致皮肤癌

  科学美国人60秒英文文本

  Ultraviolet rays don't just bronze sunseekers on the beach. Underwater, they can give hammerhead sharks a suntan. And worse—give fish skin cancer. So says a study in the journal PLOS ONE.

  Researchers caught 136 coral trout in the southern Great Barrier Reef. Fifteen percent of them had black lesions on their skin: melanoma. Pathogens, toxic chemicals or UV rays can all cause melanoma. But DNA tests ruled out the presence of pathogens. And the fish were caught in the pristine waters of a marine sanctuary, so pollution wasn't to blame.

  Turns out, the trouts' cancer cells looked just like those of fish who'd been hit with UV radiation in the lab. So the researchers concluded that sunshine was the culprit. Makes sense, they say, because these trout live near the world's biggest hole in the ozone layer—meaning more exposure to UV rays.

  Another recent study, this one in the journal Science, says the severe storms delivered by climate change could punch new holes in the ozone layer, upping our dose of radiation on land and at sea. And that's no fish story.

  中文翻译请点击下一页

本文关键字: 托福听力 科学美国人

托福辅导

关注新东方在线托福

托福机经·Official题目练习

考前重点突破·听说读写海量资料

更多资料
更多>>
更多内容

免费获取托福备考大礼包

微信扫描下方二维码 立即领取

托福辅导
更多>>
更多公益讲座>>
更多>>
更多资料