jellyfish dissection |
Structure/Function:
The jellyfish has two simple body plans, a medusa and a polyp form. The polyp attaches itself and remains sessile. They are asexual, and reproduce by budding. They lack organs, but have specialized cells that are organized into tissues. To eat, cilia line a gastrovascular cavity, and they move food, which gets digested by vacuoles. Jellyfish breathe through diffusion and have radial symmetry about the surface of the mouth.
Ecology:
Jellyfish bloom formation is a intricate process that depends on ocean currents, nutrients, sunshine, temperature, season, prey, reduced predation, and oxygen concentrations. Ocean currents tend to congregate jellyfish into large swarms or "blooms", which consist of hundreds or thousands of individuals. Blooms can also result from unusually high populations in some years. Jellyfish are better able to survive in nutrient-rich, oxygen-poor water than competitors, and thus can feast on plankton without competition. Jellyfish may also benefit from saltier waters, as saltier waters contain more iodine, which is necessary for polyps to turn into jellyfish.
The jellyfish has two simple body plans, a medusa and a polyp form. The polyp attaches itself and remains sessile. They are asexual, and reproduce by budding. They lack organs, but have specialized cells that are organized into tissues. To eat, cilia line a gastrovascular cavity, and they move food, which gets digested by vacuoles. Jellyfish breathe through diffusion and have radial symmetry about the surface of the mouth.
Ecology:
Jellyfish bloom formation is a intricate process that depends on ocean currents, nutrients, sunshine, temperature, season, prey, reduced predation, and oxygen concentrations. Ocean currents tend to congregate jellyfish into large swarms or "blooms", which consist of hundreds or thousands of individuals. Blooms can also result from unusually high populations in some years. Jellyfish are better able to survive in nutrient-rich, oxygen-poor water than competitors, and thus can feast on plankton without competition. Jellyfish may also benefit from saltier waters, as saltier waters contain more iodine, which is necessary for polyps to turn into jellyfish.