What is the class of jawless chordates?
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Super class of jawless vertebrates--Agnatha\n\nIt is further classified into 2 classes--\n\n1)Ostracodermi---extinct\n2)Cyclostomata -- the circular mouthed fishes. eg. Myxine(Hagfish) & Petromyzon(Lamprey).
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Um, mollusca is not a class...\n\nMollusca is a phylum, and bivalvia is a class under that phylum. \n\nThe major mollusk classes are Gastropoda (snails and slugs),  Bivalvia (clams, mussels, and shipworms), Cephalopoda (squid, octopuses, cuttlefish, and nautilus), Polyplacophora (chitons), Scaphopoda (tooth shells), Monoplacophora (a single-shelled animal), and the little-known Aplacophora (a questionable mollusk).\n\nBivalves have two shells, or valves, that are compressed on either side of the body. The shells are made from the excretions of the mantle as in gastropods, but are very different in shape and some functions.\nThe two shells enclose most of the body, and strong muscles inside the shell keep the two valves tightly closed. The shells open only to take in and release water or to allow the foot to extend into the sand.
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The first were some stem (basal) tetrapods, derived from crossopterygian fishes. Usually they're classified as amphibians, but they looked very different from modern amphibians. They were large (1 m or more), had fin rays on their tails and more than 5 fingers.\nDo a web search for Acanthostega and Ichthyostega.
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One of the features taken as evidence that two organisms share a common ancestor is the possession of a number of unique traits that are found in those organisms, and are not found in other groups of organisms.\n\nThe following is a (partial) list of the characters shared by all chordates (the phylum to which vertebrates belong)\n\n- Possession of a notochord (which is a dorsal axial rod of vacuolated muscular cells surrounded by a connective tissue which forms in the blastocyst from the roof of the archenteron).  The notochord functions as a skeleton and resists deformation when muscles contract.\n\n- Pharyngeal gill slits (originally for filter feeding, also for respiration)\n\n- Dorsal hollow nerve cord derived by invagination of ectoderm along the dorsal midline, sometimes with anterior expansion (brain)\n\n- Postanal tail (major locomotory organ in most chordates)\n\n- Subpharyngeal gland, which is secretory tissue in the endoderm of the pharynx floor (endostyle in protochordates, thyroid gland in 'higher' chordates)\n\n- Ventral heart\n\n- Segmented body with segmented axial muscles, axial skeleton, gill arches, nerves, aortic arches\n\n- Ectodermal ciliated canal (endocrine function, pituitary in 'higher' chordates)\n\nIn addition, there are several features unique to the the vertebrates:\n\n- Neural crest cells (arising from neural groove, become melanocytes, sensory neurons etc.)\n\n- Endoskeleton of bone and/or cartilage\n\n- 3 part brain\n\n- Muscular pharyngeal pump\n\n- Jointed internal skeleton (unique in Animal Kingdom)\n\n- Unsegmented gonads\n\n- Usually with a skeletal cylinder protecting the dorsal hollow nerve cord (i.e. vertebrae)\n\n- Pharynx is chiefly respiratory\n\n- Gas bladder for buoyancy control and respiration (in most)\n\n- Paired jaws (in most)\n\n- Paired appendages (in most)\n\n- Cranium protecting the brain (poorly developed in some)\n\nAll of these features are shared between all the vertebrates, from nasty lamprey and disgusting hagfish to cute kitty cats and arrogant humans to giant blue whales and extinct ankylosaurs.\n\nThe possession of all of these features suggests that these organisms share a common ancestor from which they inherited all these traits.
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Protostomes (from the Greek: first the mouth) are a taxon of animals. Together with the deuterostomes and a few smaller phyla, they make up the Bilateria, mostly comprising animals with bilateral symmetry and three germ layers. The major distinctions between deuterostomes and protostomes are found in embryonic development. In protostome development, the first opening in development, the blastopore, becomes its mouth. In deuterostome development, the blastopore becomes the animal's anus. Protostomes have what is known as spiral cleavage which is determinate, this meaning that the fate of the cells is determined as they are formed. This is in contrast to deuterostomes which have radial cleavage that is indeterminate.\n\nDeuterostomes (taxonomic term: Deuterostomia; from the Greek: "second mouth") are a superphylum of animals. They are a subtaxon of the Bilateria branch of the subregnum Eumetazoa, and are opposed to the protostomes. Deuterostomes are distinguished by their embryonic development; in deuterostomes, the first opening (the blastopore) becomes the anus, while in protostomes it becomes the mouth.\n\nThere are three phyla of deuterostomes:\n\n    * Phylum Chordata (vertebrates and their kin)\n    * Phylum Echinodermata (starfishes, sea urchins, sea cucumbers, etc.)\n    * Phylum Hemichordata (acorn worms and possibly graptolites)\n\nThe phylum Chaetognatha (arrow worms) and the isolated genus Xenoturbella may also belong here. Extinct groups may include the phylum Vetulicolia. The term Ambulacraria is sometimes used for the phyla Echinodermata and Hemichordata, as well as Xenoturbella.\n\nIn both deuterostomes and protostomes, a zygote first develops into a hollow ball of cells, called a blastula. In deuterostomes, the early divisions occur parallel or perpendicular to the polar axis. This is called radial cleavage, and also occurs in certain protostomes, such as the lophophorates. Cleavage is indeterminate - the cells' fates are not determined early on. Thus if the first four cells are separated, each cell is capable of forming a complete small larva, and if a cell is removed from the blastula the other cells will compensate.\n\nIn deuterostomes the mesoderm forms as evaginations of the developed gut that pinch off, forming the coelom. This is called enterocoely.\n\nBoth the Hemichordata and Chordata have gill slits, and primitive fossil echinoderms also show signs of gill slits. A hollow nerve cord is found in all chordates, even tunicates (even if it disappears in the adults). Some hemichordates also have a tubular nerve cord. In early embryonic stage it looks like the hollow nerve cord of chordates. Because of the degenerated nervous system of echinoderms it is not possible to discern much about their ancestors in this matter, but based on different facts it is quite possible that all the present deuterostomes evolved from a common ancestor which had gill slits, a hollow nerve cord and a segmented body. It could have resembled the small group of Cambrian deuterostomes named Vetulicolia.
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first they are all animals\nsponge\n(cells not differentiated into tissue)\njellyfish\n(single opening to digestive tract)\ntapeworm\n(tissue differentiation but no symmetry)\nstarfish\n(complex tissue differentiation, radial symmetry)\n\nearthworm\n\nsnail\n\ncentipede\n\nhuman
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The three species of Lagidium (Lagidium peruanum, L. viscacia, and L. wolffsohni) share a number of cranial features which classify the Family Chinchillidae:  They are hystricognathous (the angular process where the masseter arises is lateral to the plane of the rest of the jaw), and strongly hystricomorphous (in which the infraorbital foramen is enlarged for attachment of the medial masseter muscle).  The mandibles have no masseteric crest, the lacrimals are large and the lacrimal canal opens on the side of the rostrum.  The auditory bullae are enlarged.  The teeth have a pattern of 1/1, 0/0, 1/1, 3/3 = 20) and are hypodont and rootless.  Their molars have two or three closely packed lamellar plates.\n\nSome workers have suggested that the large genetic distances (between 5.9% and 8.9%) between the described species may mean that there are more than the three species of Lagidium that are currently recognized.  Other authors include L. peruanum within L. viscacia, meaning only two species in the Genus.\n\nIf you are looking for the specific characters used to distinguish the different species, I would recommend checking out the following references:\n\nWoods, C. 1993.  Suborder Hystricognathi. Pp. 771-806 in Mammal species of the world: a taxonomic and geographic reference (D.E. Wilson and D.M. Reeder, eds.). Smithsonian Institution Press, Washington, D.C.\n\nAnderson, S. 1997.  Mammals of Bolivia, taxonomy and distribution.  Bulletin of the American Museum of Natural History 231:1-652.
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cnidarians have a sac called a gastovascular cavity where digestion occurs. There's only one opening to it that acts as both a mouth and anus.
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>>>>>> Only vertebrates have teeth.\n\nThat isn't true. Lampreys have teeth and are not vertebrates. The radulae of many molluscs also have teeth.\n\nThe rest of your answer was spot on though.
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What a cool project!  So to answer one of your questions, the crucial distinction among your phyla will be whether or not they're chordates -- which of course includes the vertebrates (but also some invertebrates such as sea squirts and certain worms).  \n\nSo your bipedal wolf (I'm assuming the missing d was a typo, but if "bipeal" is a word from your universe, please let me know) would be phylum chordata, class vertebrata, order mammalia, family canidae, genus canus, species lupus bipedalis (and I'm envisioning something like a cross between Lawrence Talbot and Speaker-to-Animals, without retractible claws).  But that's just off the top of my head.\n\nOne thing I've discussed with my ten-year-old son is the absence of hexapod vertebrates -- e.g. flying horses, winged dragons, etc.  If you were closer, I'd invite you over for coffee and an all-day discussion of where to classify them, and how they evolved.  Since all terrestrial vertebrates have essentially the same structure, it's clear they all shared a common ancestor which makes hexapodal vertebrates, sadly, impossible in our known universe -- so was there a hexapodal (imaginary) marine vertebrate who also scuttled across the floors of silent seas before crawling out of the surf and saying "Hey, the carcharodons can't get me here!  Kewl!"?  ...Which of course suggests all sorts of hexapodal marine vertebrates that shared the same skeletal architecture.  Ooooh, fun.\n\nAnd the final question... so zoology is the study of animals.  There's also cryptozoology, which I've described flippantly as "the study of imaginary animals."  But of course, it's more technically the study of animals that may or may not exist.  So what would we call your zoology, which is the study of animals you've intentionally invented?  Oh, of course, poeiazoology (-poeia, meaing to construct -- as in mythopoeia, the term Tolkien invented to describe the invention of mythologies.)\n\nAnd on that note, elen sila lumen omentielvo!
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You are looking for the Cnidaria corals I believe. In the early Paleozoic (cambrian to silurian) they diversified into tabulate corals, rugose corals, and heliolitid corals. All these forms were wiped out at the end of the Permian Period, in a mass extinction event that claimed something like 95% of all marine invertebrate species.\n\nDescriptions of these types of corals are linked in this page:\nhttp://www.ucmp.berkeley.edu/cnidaria/cnidariafr.html\n\n\nTHis page may also be a big help to you:\nhttp://www.paleoportal.org/fossil_gallery/taxon.php?taxon_id=55
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You are clearly referring to the Class Cephalopoda (squids, octopi, etc.).  It is in the Phylum Mollusca.  Most molluscs, however, have moderate to poor eyesight relative to arthropods and cephalopods (snails and clams are molluscs) so saying the Phylum Mollusca is the correct choice is a bit off.
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I would look here for your answer and/or a link that could get you your answer http://en.wikipedia.org/wiki/Vertebrate\n\nGood Luck!!!
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I believe, that you are looking for amoeba.\nAmoeba's are from the kingdom: Zooplankton,  which has animal like characteristics. The Amoeba, in particular, belongs to the phylum: sarcodina which have characteristics such as having a coinceboid shape (no shape), and being able to flow by extending it's cell membrane to form false feet (pseudopod).\n\nBut, there are still several others that can be classified in this category: Paramecium cordatum (from the phylum: ciliophora), Trypanosoma gambiensis (from the phylum: mastigophora), and Plasmodium vivox (from the phylum: sporozoa)\nAs you see, there is more then one choice in this matter.\n\nHope this helps!
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prokaryotic cells are the ONLY cells on that list that have no nucleus or organelles....\n\n...someone hasn't been paying very much attention in class....
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They are all invertebrates, ie they don't have backbones
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Kingdom: Animalia\nPhylum: Chordata\nClass: Mammalia\nOrder: Carnivora\nFamily: Felidae\nGenus: Panthera