Solution:
The largest and most prominent stage in the life cycle of most members of the cnidarian class scyphozoa (true jellyfish) is the Phylum Cnidaria.
Phylum Cnidaria includes animals that show radial or biradial symmetry and are diploblastic: they develop from two embryonic layers. Nearly all (about 99 percent) cnidarians are marine species.
Cnidarians contain specialized cells known as cnidocytes (“stinging cells”), which contain organelles called nematocysts (stingers). These cells are present around the mouth and tentacles, serving to immobilize prey with toxins contained within the cells. Nematocysts contain coiled threads that may bear barbs. The outer wall of the cell has hairlike projections called cnidocils, which are sensitive to touch. When touched, the cells are known to fire coiled threads that can either penetrate the flesh of the prey or predators of cnidarians, or ensnare it. These coiled threads release toxins into the target that can often immobilize prey or scare away predators.
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