新东方在线网络课堂 托福 新东方在线 > 托福 > 托福精选 > 正文

科学美国人60秒:鲨鱼体内含毒素或威胁类-托福听力下载

2016-11-18 15:46:01 来源:网络托福资料下载

点击查看>>科学美国人60秒音频:鲨鱼体内含毒素或威胁类

  科学美国人60秒中英文翻译:鲨鱼体内含毒素或威胁类

  科学美国人60秒英文文本

  This is Scientific American — 60-Second Science. I'm Christopher Intagliata.

  Living at the top of the food chain, sharks can accumulate dangerous levels of methylmercury. So much that pregnant women and children are advised not to eat shark at all. But sharks can accumulate another toxin too, called BMAA, which has been linked to the development of neurodegenerative disease. Which could be bad news for shark eaters.

  "Mercury in combination with BMAA is a one-two punch." Deborah Mash, a professor of neurology at the University of Miami's Miller School of Medicine. "These are two synergistic toxins. So even if there are low levels of exposure from the mercury or the BMAA, when humans are exposed to both of these toxins, then they will have a synergistic effect on the nervous system."

  BMAA starts out in cyanobacteria, and travels up the food chain through crabs and shrimp and fish. And, as previous studies have shown, makes all the way to sharks. What Mash and her colleagues wanted to know was how widespread the problem was, and if the chemical often appeared alongside mercury. So they analyzed fin and muscle samples from 10 species of shark—55 individuals in all—from the Atlantic and Pacific Oceans. And they found BMAA and mercury in all 10 species. Suggesting that exposure to that "one-two punch" could be pretty common. The results are in the journal Toxins.

  It's still not clear at this point what sort of risk this occasional exposure through food might have. Still, Mash isn't waiting.

  "I myself would not want to be exposed to BMAA or methyl mercury in my diet by eating shark fin or shark meat or taking shark cartilage products. We already know that mercury is toxic to our health. And we already know that BMAA plus mercury is a very bad mix for the brain. So people need to be concerned, and I think that's not only for the benefit of us as consumers, but also to the poor sharks, who are threatened with extinction."

  Conservationists have argued for years that sharks should be spared. Maybe now that it's us who are threatened... people might finally start to leave them alone.

  Thanks for listening for Scientific American — 60-Second Science Science. I'm Christopher Intagliat

  中文翻译请点击下一页

本文关键字: 科学美国人60秒 科学60秒下载 托福听力

为你特别匹配的托福超值课程,快速提分先人一步!
  • 【直播课程】托福考前10天,如何才能自救

    【直播课程】托福考前10天,如何才能自救

    适合人群:备战托福的筒子们!!!

    课时:8 课程有回放~

    查看详情
  • 大学生旗舰直达冲100分

    【知心托福】大学生旗舰直达冲100分

    适合人群:托福目标分数100!!!

    课程特色:推送补充相应知识点,有效提升学习效率。

    查看详情
  • 【21天冲分】 21天直冲托福100+

    【21天冲分】 托福2018年8月临考急训25人班

    适合人群:参加过托福考试或基础段的学习,距离最新考试仅剩1个月时间,急需短期内快速高效冲分的考生。

    特点:全科直播24小时

    查看详情
  • TOEFL8月早练团

    【早练团】TOEFL8月早练团

    课程特色:高能学习的正确打开方式,早练早提分!

    课时:28课时(每天0.5小时,5月共上课28天)

    查看详情
  • 大学生旗舰直达班 (冲110分)

    【知心托福】大学生旗舰直达班 (冲110分)

    适合人群:托福目标分数110分!

    课时:343

    查看详情

托福人气课程推荐全部课程

最受欢迎课程 知心托福大学生旗舰直达班(冲110分) ¥8280 免费试听
知心托福中学生旗舰直达班(冲110分) ¥8280 免费试听
知心托福精品直达班(冲110分) ¥5880 免费试听
单项突破 阅读口语听力写作
托福入门 词汇语音精听三科联报
直播课堂 考前预测
致赢一对一 临考冲刺临考强化短期集训强化冲分低起点冲分零起点托管冲分
更多托福课程
新东方23年教学经验沉淀
托福考生必修课
全球首发ETS独家授权TPO全真模考精准预测
查看详情

课程试听换一换

  • 知心托福 大学生旗舰直达班 (冲110分)

    ¥8280

  • 知心托福 直达班(冲110分)

    ¥4380

  • 知心托福 精品直达班(冲110分)

    ¥5880

  • 知心托福 直达班(冲100分)

    ¥4080

  • 知心托福 精品直达班(冲100分)

    ¥5680

  • 知心托福 大学生旗舰直达班 (冲100分)

    ¥7980

  • 新东方托福全名师21天魔鬼急训冲分【8月...

    ¥7499

  • 知心托福 中学生旗舰直达班 (冲110分)

    ¥8280

分享到:

相关推荐

交流 • 下载

精品课限量免费领

  • 托福名师直播公益课
  • 北美中学直播课程
  • 托福听力备考全攻略
  • 世界大学排名榜(全球大学排名)
  • 最新美国大学排名

提分历程更多>>

实用 • 工具

托福课程排行榜本周本月

托福公开课更多>>

新东方在线托福名师宣传片 w 03分32秒
1 新东方在线托福名师宣传片
新东方在线知心托福介绍说明【热】 w 04分14秒
2 新东方在线知心托福介绍说明【热】
新东方在线唐悦宁:托福词汇遗忘规律 w 07分34秒
3 新东方在线唐悦宁:托福词汇遗忘规律
新东方在线唐悦宁:词根词缀记忆法 w 04分42秒
4 新东方在线唐悦宁:词根词缀记忆法
新东方在线唐悦宁:托福听力基础预备 w 03分30秒
5 新东方在线唐悦宁:托福听力基础预备

推荐阅读