The Life of Animals | Jellyfish | Most jellyfish undergo two distinct life-history stages (body forms) During Their Life Cycle. After fertilization and initial growth, a larval form, Called the planula, develops. The polyp is Generally a small stalk with a mouth surrounded by tentacles facing upward-like miniatures of the closely related anthozoan polyps (sea anemones and Corals), also of the phylum Cnidaria. Polyps may be solitary or colonial. Certain species of Box Jellyfish sleep on the sea bed in shallow water. Jellyfish reproduce sexually and asexually Both. Upon Reaching adult size, jellyfish spawn daily if there is enough food.
Jellyfish are usually either male or female (hermaphroditic specimens are occasionally found). In A Few species, the sperm swim into the female's mouth fertilizing the eggs within the female's body where They Remain During early development stages. In moon jellies, eggs lodge in the pits on the oral arms, the which form a temporary Brood chamber for the developing planula larvae. After a growth interval, the polyp begins reproducing asexually by budding and, in the Scyphozoa, is Called a segmenting polyp, or a scyphistoma.
A few jellyfish species can Produce New Medusae by budding directly from the medusan stage. In the second stage, the tiny polyps asexually Produce jellyfish, each of the which is also known as a medusa. A few species of jellyfish do not have the polyp portion of the life cycle, but go from jellyfish to the next generation of jellyfish through direct development of fertilized eggs. "Dried jellyfish" has Become increasingly popular throughout the world. The jellyfish is dried to Prevent from spoiling, if not dried They can Spoil within a matter of hours. Scyphozoan Only jellyfish belonging to the order Rhizostomeae are harvested for food; about 12 of the approximately 85 species.
Jellyfish prepared this way retain 7-10% of Their original weight, and the processed product contains approximately 94% water and 6% protein. Freshly processed jellyfish has a white, creamy color and turns yellow or brown During prolonged storage. In China, processed jellyfish are desalted by soaking in water overnight and Eaten cooked or raw. In Japan, cured jellyfish are rinsed, cut into strips and served with vinegar as an appetizer. Fisheries have Begun harvesting the American cannonball jellyfish, Stomolophus meleagris, along the southern Atlantic coast of the United States and in the Gulf of Mexico for export to Asia
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