There is no one set type of symmetry for sponges. Therefore, not all sponges have the same type of symmetry. Sponges can range from asymmetrical to radical symmetry.
While it is true that sponges are found in water, it is also true that sponges are found in different regions of water. For example, sponges are found both in saltwater (most common) and freshwater environments. Sponges can be found in both shallow water and along the …show more content…
However, the one feature of cnidarians that gives them their name, according to the dictionary, is that cnidarians are all stinging creatures, such as jellyfish.
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The polyp stage and medusa stage are different body forms found in the cnidarians jellyfish. The polyp stage is a fixed stage, meaning it does not move from its position. By contrast, the medusa stage is a free roaming stage, meaning it is not fixed and travels around the water.
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Based on the photo, it would appear that the hydra is exhibiting the polyp stage.
The part of the hydra that contains the stringing cells would be the tentacles of the hydra.
The stinging cells are used primarily for catching prey and protection. When another creature comes into contact with the tentacles containing the stinging cells, depending on the size of the creature, it will either become paralyzed from the venom from the string or be scared away by the pain of the sting. So the cnidarian in question either acquired a meal or avoided danger.
Yes, because jellyfish are a cnidarian and all cnidarians are capable of