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14.5: Introduction to Phylum Cnidaria

  • Page ID
    44727
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    What you’ll learn to do: Identify the common characteristics of phylum Cnidaria

    Cnidarians represent a more complex level of organization than Porifera. They possess outer and inner tissue layers that sandwich a noncellular mesoglea. Cnidarians possess a well-formed digestive system and carry out extracellular digestion. The cnidocyte is a specialized cell for delivering toxins to prey as well as warning off predators. Cnidarians have separate sexes and have a lifecycle that involves morphologically distinct forms. These animals also show two distinct morphological forms—medusoid and polypoid—at various stages in their lifecycle.

    Contributors and Attributions

    CC licensed content, Original
    • Introduction to Phylum Cnidaria. Authored by: Shelli Carter and Lumen Learning. Provided by: Lumen Learning. License: CC BY: Attribution
    CC licensed content, Shared previously

    14.5: Introduction to Phylum Cnidaria is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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