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托福阅读材料推荐:生物体发光的作用

2016-07-20 14:16:26来源:网络

  Alien spaceship?

托福阅读材料推荐:生物体发光的作用

  Alien spaceship?Photo:

  Image: M. Youngbluth, OAR/National Undersea Research Program (NURP); Harbor Branch Oceanographic Institution

  Touch for the jellyfish is a big no-no, a warning sign: Upon touch, jellyfish will light up, warning predators to stop doing what they’re doing and exposing them at the same time to their potential predators.

  Who’s bothering whom? Two longfin bannerfish nibbling on a jellyfish:

  Jellyfish and fishPhoto:

托福阅读材料推荐:生物体发光的作用

  Image: Dr. Dwayne Meadows, NOAA/NMFS/OPR

  Jellyfish produce bioluminescence through a reaction of the two chemicals luciferin and luciferinase. When triggered (e.g. through touch), luciferin gets oxidized by luciferinase. Their reaction results in a photoprotein that causes the bluish glow. Some jellyfish have an additional protein, the green fluorescent protein (GFP), which converts the blue light to green. A recently discovered and yet unnamed Cnidarian in the genus Erenna even emits fluorescent red. Bring on the light show!

  Sources: 1, 2, 3

  We’ll even throw in a free album.

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