Sponge Dissection: The sponge is a simple creature that either has radial symmetry or is asymmetrical. They have no cephalization, but they do have suspension feeders. For reproduction, some are asexual and others release sperms and eggs in to the water to find each other and fertilize. Their skeletons are made up of spicules. They make good habitats for marine life because they improve nutrient cycles and reduce the amount of nitrogen in coral reef systems. They form mutual relationships with some organisms. For example, if they live on a scallop, the scallop provides it good living conditions and the sponge provides some form of protection for the scallop. The sponges irregular shape makes them an ideal home for animals like snails, sea stars, sea cucumbers, etc. Many types of algae live on sponges and provide oxygen to the sponge while the sponge offers protection. Since sponges live on the ocean floor they receive little sunlight. Their spicules are shaped in a cross pattern which magnifies the light and allows sponges to survive in a wider range of habitats. 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. 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. Squid Lab The molluscan is far more complex the the rest of the phyla we have studied thus far. Species in molluscan have specialized tissues and organs, such as Ganglion ( a primitive brain), and tissues like the color changing chromatophores. I also has bilateral symmetry allowing for a more sophisticated body plan. Earthworm Lab:Earthworms are very complex creatures. They possess bilateral symmetry, extracellular digestion, and cephalization. Earthworms have an one- way digestive system, a mouth, crop, intestines, and other organs. They have a closed circulatory system, and respire through their skin. They are also hermaphrodites because they poses both female and male sex organs. . Grasshopper Lab The phylum Mollusca is more advanced than Porifera, Cnideria, and Annelid. They have developed a way of communicating, wings, and an exoskeleton. The grasshopper also has sensory organs like its antenna and its compound eyes. The grasshopper has a developed method of auditory communication, an exoskeleton, and wings. It has a complex sensory system, which includes antenna and compound eyes. It has bilateral symmetry and an open circulatory system. It reproduces sexually, and has three body regions. Perch Lab The general body shape of a perch is a fish. It has fins a head, tail, and many other features that help it live in the wild. The gills take out any contaminate from the water and filter the oxygen. The scales are slimy and shiny. They face towards the tail. These things provide a streamline surface and reflect light. reflecting light may allow them to blend with their environment. The perch has two nostriles. They are allot smaller and don't protrude. They are only used for scent, not breathing. A charectaristic of the fish's gill that could make it an efficient respitory organ is that it's close to the mouth. That way, oxygen doesn't have to travel all the way to the back of the fish. The lateral line looks like a very small line on the back. |