The Zone Without A Backbone

*The zoo filled with creepy and cool invertebrates.

CNIDARIANS

    Examples and Phylum:

    • Cnidarians include many different animals; like jellyfish, anemones, hydra, and polyps. They are all in the phylum Cnidaria. Developments: 

     

     

    • Cnidarians are far more complex than sponges. They have invented sensitive tentacles, a mouth, a stomach, movement, stinging cells, and a nerve net.
    • Their sensitive tentacles have given them the ability to reach out and feel the world.
    • Their mouth allows them to eat bigger food easier.
    • Their stomach gave them the ability to digest all of their food.
    • Movement allowed cnidarians to escape danger, travel to a mate, and travel to food.
    • Their nerves allowed them to react to their surroundings and protect themselves.
    • The cnidarians stinging cells allowed them to protect themselves from predators and hunt prey.
    • Cnidarians feed themselves by waiting until their prey touches its tentacles. And then the nematocysts (stinging cells) inject the venom that paralyzes/ kills the prey. The tentacles then proceed to put the paralyzed prey into the mouth to be digested alive.

    Body Plans:

    • Cnidarians come in 2 different body plans; Polyp, and Medusa.
    • The polyp body plan has one opening at the top. Most polyps don't move, but they can pop out of the ground and swim away from predators.
    • The medusa body plan has one opening at the bottom. Almost all medusas swim in a pulsing motion throughout the ocean.

    Reproduction:

    • Jellyfish reproduce quite strangely. They reproduce sexually and asexually. The cycle starts when a polyp attaches itself onto a rock. Soon the polyp will start "budding" baby medusas off of its head. The medusa jellyfish will grow bigger then travel to a breeding ground. The male jellyfish will leave a string of sperm in the ocean and then a female jellyfish will go towards the sperm, then ingest it.

    Importance of Cnidarians:

    • Cnidarians are important because they make coral reefs which are a habitat to other animals and a tourist attraction to humans. They also provide a home for algae which creates oxygen that we breathe. The coral reefs are also important because the polyps, algae, and animals in that habitat are a major food source for other animals.

      You Rule Cnidarians!!    

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