Jellyfish

Today, i want to introduce an inconspicuous but dangerous sea animal - jellyfish.

Jellyfish is invertebrate ,a member of Phylum Cnidaria(刺絲胞動物門).They are consisted of 95 percent of water, 3 percent of salt, and 2 percent of protein. They can emit carbon monoxide to make the umbrella liking head expand. Strangely, they are lacking of heart, blood, skeleton, lung, and gill. The way of inspiring is directly use their external organizations to exchange oxygen and carbon dioxide. Most importantly, there are many nematocysts(刺絲囊) distributed on their tentacle.

There are more than 2 hundred kinds of jellyfishes in the world. The biggest is Cyanea capillata(獅鬃水母),whose radius can be up to 1 meters and tentacle can be up to 35 meters!!

amazingly big !!

 

However, the smallest jellyfish only can develop to 12 millimeters, which is really inconspicuous to our eyes.Besides, jellyfishes can glow in the water by a wonder protein, Ai Kuiming(埃奎明). When this protein is combined with Calcium, it will emit strong, blue light. The more Ai Kuiming jellyfishes have, the stronger light they emit, and averagely each jellyfish has only fifty milligrams Ai Kuiming.

Finally, i am going to talk about the toxicity of this interesting creature. Contact with their tentacle can trigger millions of  nematocysts to pierce the skin and inject venom, which can lead to ache, swell, and even nausea, and sometimes will last for several weeks. If one have difficult to inspire after being pieced, we should implement artificial inspiration immediately ,inject Cardiac(強心劑), and go to hospital as fast as we could. Never ignore them, or one might lose his life if the condition become too bad.