Jellyfish looks weak, but it is an untouchable carnivore. Zooplankton, shrimp and fish are all prey of jellyfish. Most jellyfish have long, soft tentacles covered with stinging cells. In addition to jellyfish, corals, anemones and corals also have stinging cells, so they are all classified as stinging animals. However, because jellyfish have a wider range of activities than other echinoderms, they often float on the sea surface and are pushed to the beach by waves, causing more people to be injured accidentally, and their lethality should not be underestimated ... So when it comes to echinoderms, many people think of jellyfish for the first time.
The stinging cells on the tentacles of jellyfish are very small and contain stinging sacs for storing stinging filaments. When the stinging cells are physically stimulated, a small number of stinging cells will release the stinging silk in the stinging silk sac in a very short time and shoot at the prey. Moreover, the body fluids oozing out after the prey is stabbed will stimulate more stinging cells to emit stinging silk through chemical reaction. Spinning will inject jellyfish venom into prey and paralyze prey. Finally, the tentacles of jellyfish roll their prey into their mouths for chemical digestion and a full meal to get the energy needed for survival.
Not only the hunting efficiency is amazing, but also the shapes of barbed wire are various, such as hollow barbed wire like a needle, barbed wire curled like a spring to increase the ejection force, sticky barbed wire covered with mucus and so on. However, these deadly weapons of jellyfish, stinging cells, are disposable and discarded after use. At the same time, the constantly updated stinging cells keep the jellyfish fighting. Different jellyfish have different degrees of lethality. Most jellyfish are not fatal, but some jellyfish are frightening, such as box jellyfish (as the name implies, its shape is like a square box), and its toxicity can kill the injured in a few minutes. Take Chiropsalmus quadrigatus, a common box jellyfish in Okinawa in summer, as an example. When people come into contact with bobo jellyfish, they will feel the pain of electric shock, and in severe cases they will faint and even die on the spot. This is one of the adverse reactions caused by jellyfish venom entering the human body.