How do vertabrates and invertabrates differ?
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Well, the answer also lies in the modern theory of evolution. According to this, vertebrates are actually highly adapted invertebrates that diverged about 500 million years ago, with the development of the first fishes. Biologically speaking, vertebrates have a bony or cartilogenous backbone that protects the spinal cord from injury, while invertebrates either don't have a backbone, or don't have a spinal cord. As the early invertebrates adapted, a feature appeared that was favored as time went on, a rigid structure surrounding the spinal cord and brain to protect them and adding to the rigidity of the body as a whole. As more time went by, muscles and tendons used these as attaching points. Fish grew bigger, stronger, and more adapted to the new structure, until a group of lungfish-like creatures adapted to live on land. There, the backbone was used as an anchoring point for several bony appendages, and became thicker  and stronger in response to the pull of gravity. It became strong enough for the needs of each subsequent animal that evolved later, and that leads us to today.
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i`m not sure...\nbut i think so...\n\nthere should be differences between exoderm, endoderm and mesoderm cells...
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http://scholar.google.com/scholar?q=penetrating%20injuries%20of%20the%20vertebral%20column"?&hl=en&lr=\n\nThe above link has several scholarly websites on the subject.\n\n\nVertebral column\nFrom Wikipedia, the free encyclopedia\nJump to: navigation, search\n \nThe vertebral column seen from the side \nDifferent regions (curvatures) of the vertebral columnIn human anatomy, the vertebral column (backbone or spine) is a column of vertebrae situated in the dorsal aspect of the abdomen. It houses the spinal cord in its spinal canal.\n\nCurves\nViewed laterally the vertebral column presents several curves, which correspond to the different regions of the column, and are called cervical, thoracic, lumbar, and pelvic. The cervical curve, convex forward, begins at the apex of the odontoid (tooth-like) process, and ends at the middle of the second thoracic vertebra; it is the least marked of all the curves. The thoracic curve, concave forward, begins at the middle of the second and ends at the middle of the twelfth thoracic vertebra. Its most prominent point behind corresponds to the spinous process of the seventh thoracic vertebra. The lumbar curve is more marked in the female than in the male; it begins at the middle of the last thoracic vertebra, and ends at the sacrovertebral angle. It is convex anteriorly, the convexity of the lower three vertebrae being much greater than that of the upper two. The pelvic curve begins at the sacrovertebral articulation, and ends at the point of the coccyx; its concavity is directed downward and forward. The thoracic and pelvic curves are termed primary curves, because they alone are present during fetal life. In the early embryo, the vertebral column is C-shaped, and the cervical and lumbar curvatures are not yet present in a newborn infant. The cervical and lumbar curves are compensatory or secondary, and are developed after birth, the former when the child is able to hold up its head (at three or four months), and to sit upright (at nine months), the latter at twelve or eighteen months, when the child begins to walk.\n\nThe vertebral column also has a slight lateral curvature, the convexity of which is directed toward the right side. This may be produced by muscular action, most persons using the right arm in preference to the left, especially in making long-continued efforts, when the body is curved to the right side. In support of this explanation it has been found that in one or two individuals who were left-handed, the convexity was to the left side. This curvature is regarded by others as being produced by the aortic arch and upper part of the descending thoracic aorta – a view which is supported by the fact that in cases where the viscera are transposed and the aorta is on the right side, the convexity of the curve is directed to the left side.\n\n\nSurfaces\n\nAnterior surface\nWhen viewed from in front, the width of the bodies of the vertebrae is seen to increase from the second cervical to the first thoracic; there is then a slight diminution in the next three vertebrae; below this there is again a gradual and progressive increase in width as low as the sacrovertebral angle. From this point there is a rapid diminution, to the apex of the coccyx.\n\n\nPosterior surface\nThe posterior surface of the vertebral column presents in the median line the spinous processes. In the cervical region (with the exception of the second and seventh vertebrae) these are short and horizontal, with bifid extremities. In the upper part of the thoracic region they are directed obliquely downward; in the middle they are almost vertical, and in the lower part they are nearly horizontal. In the lumbar region they are nearly horizontal. The spinous processes are separated by considerable intervals in the lumbar region, by narrower intervals in the neck, and are closely approximated in the middle of the thoracic region. Occasionally one of these processes deviates a little from the median line — a fact t
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The functional organization of the cerebellum\n \nSchematic representation of the major anatomical subdivisions of the cerebellum. Superior view of an "unrolled" cerebellum, placing the vermis in one plane\n\nVermis\nThe vermis receives its inputs mainly from the spinocerebellar tracts from the trunk of the body. These tracts carry to the vermis information on the position and balance of the torso. The vermis sends projections to the fastigial nucleus of the cerebellum, which then sends output to the vestibular nuclei. The vestibular nuclei are structures important for the maintenance of balance.\n\nIntermediate zone\nThe intermediate zone receives input from the corticopontocerebellar fibers that originate from the motor cortex. These fibers carry a duplicate of the information that was sent from the motor cortex to the spine in order to effect a movement. The intermediate zone also receives sensory feedback from the muscles. These two streams of information are integrated by this region, allowing for the feedback comparison of what the muscles are supposed to be doing with what they are actually doing.\n\nLateral zone\nThe lateral zone receives input from the parietal cortex via pontocerebellar mossy fibers regarding the location of the body in the world. The large numbers of feedback circuits allow for the integration of this body position information with indications of muscle position, strength, and speed\n\nmore especif info:
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...\n\nThe bony arches of the vertebrae have two types of projection: one, called the spinous process, extends backwards from the arch in the mid-line (it is these spinous processes which are felt all down the back); the other, the transverse processes, extend laterally on each side from a position posterior to the intervertebral foramen.\n\nIf one now considers the vertebral column as a structural unit, one sees the column of vertebral bodies anteriorly, joined by the intervertebral discs as bricks are joined by mortar, with the bony arches behind. These bony arches have paired pedicles which enclose the intervertebral foramina on each side just behind the vertebral bodies. Farther back on each side one encounters the transverse processes, and finally in the mid-line of the back, the spinous processes. The whole column is bound together with various ligaments of great strength, on the anterior and posterior surfaces of the vertebral bodies and on the bony arches, their processes, and their joints. The muscles further strengthen and cushion the vertebral column.\n\nWithin the vertebral column, the circles formed by the bony arches described above are aligned to constitute a canal, called the spinal canal. The spinal canal contains the spinal cord, the trunk of nerves which is in continuity with the brain above. Neither the brain nor the spinal cord are in contact with the bones which protect them. These delicate nerve structures are completely enveloped by three concentric membranes, the meninges; respectively, the dura mater, the arachnoid, and the pia mater.\n\n...
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the 7 living classes of vertebrate are distuingished mostly on the basis of their skeletal system\n\na) agnatha - consist of jawless fish that don't have scales ex. lampreys and hagfish\nb) chondrichthyes - consisting of hard rubber like cartilages ex. sharks and rays\nc) osteichthyes - bony fish ex. tuna, bass, salmon\nd) amphibia - lives under water and part land ex. frogs, toads, salamander\ne) reptilia - have lungs to breathe on land and skin does not need to be wet ex. turtles, lizards, alligators\nf) aves - include all birds\ng) mammalia - large animals ex. dogs, cats, humans
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oh i know this so well,read it for my exam ,ok here it goes:\n    \n\n~ types of cells involved in epiboly are micromeres whereas in emboly ,for involution or rolling in of cells ,the cells involved are micromeres and for ivagination or in pushing of cells,the cells involved are macromeres or megameres.\n\n~ location for the process of epiboly ,in the forming gastrula , is animal zone or pole,whereas for emboly,involution it is equatorial zone and for invagination it is vegetal zone.\n\n~ the germ layer formed after epiboly is the ectoderm and in the case of embol,involution process gives rise to chordamesoderm\nand after the process of invagination,endoderm is formed.\n\n\nim sorry can't write by drawing columns so wrote it this way,hope u understood what i wrote.all the best for ur studies,any help u can contact me! :)
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Actually, amarsupials are mammals. They are a sub group just as is the other group that includes the platapus and echidna (can't remember the name of this group).\n\nThe difference is that the young is succled in a pouch. \n\nThey are born alive, not in egg, they are warm blooded, as all mammals do/are.
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A lot of vertebrate metamorphosis study outside of amphibians is aimed at fish. Fish to look up include lamprey and flatfish. Vertebrate metamorphosis tends to be attributed to thyroid hormones. Unfortunately a lot of articles are in journals rather than online. The online stuff tends to be summaries/abstracts.\n\nAn introduction to the whole idea. It starts with invertebrates, but shows how the systems evolve up to vertebrates:\nhttp://www.thyroidmanager.org/Chapter1/index.html\n\nSpecific articles on the subject, mainly focusing on fish:\nhttp://www.sgnis.org/publicat/papers/az37_441.pdf\nhttp://findarticles.com/p/articles/mi_qa3746/is_199804/ai_n8798333\nhttp://www.ciwemb.edu/labs/schreiber/index.php\nhttp://www.findarticles.com/p/articles/mi_qa3746/is_199712/ai_n8778286\n\nA scientific journal article that might be useful if you can find it:\nWald, George (1958) The significance of vertebrate metamorphosis. Science 128:1481.\n\nYou may find more of interest in the references sections of the links provided.
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First off, it's only the number of _cervical_ (neck) vertebrae of mammals that is fixed at 7, not all the other vertebral types. There are exceptions, such as the tree sloths with 6 or 9 vertebrae, and a manatee species with 6, but the number 7 is consistent in most species of mammals, from giraffes (although there was an interesting question about it here) to dwarf shrews. \n\nA recent hypothesis (1999) about the fixed nº of cervical vertebrae is related to evolutionary developmental (evo-devo) aspects. Apparently, in mammals the genes that regulate the development of the skeleton (Hox genes) are also linked to the proliferation of cell lines (which is in turn related to the origin of cancer). Thus, any change in the nº of vertebrae could bring about deletereous (negative) changes in the control of cell multiplication, and would be constrained by natural selection because although the fixed nº of cervical vertebrae is not particularly advantageous, the possibility of tumor development is decidedly disadvantageous.\n\nAnd with respect to canislupus' question: If there is such a constraint, maybe the different number of cervical vertebrae in sloths and manatees gives advantages that offset the potential problems. In the case of sloths, I can easily see that more vertebrae enable greater rotation angle of the head (these animals are very impressive when they move). In the case of manatees, I cannot think of an evident advantage, but then again, I don't know much about manatees.\nSee the article at the first link.\n\n------------\nUpdate: I've checked other sources and it appears that both manatees and sloths share one trait: low basal metabolism. This could allow changes in the regulatory Hox gene without the threat of cancer (see second link)\n------------\nUpdate 2: Canislupus, this is new knowledge for me too. That's why I like Answers :-)
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The Chordata is the animal phylum with which everyone is most intimately familiar, since it includes humans and other vertebrates. However, not all chordates are vertebrates. \n\nAll chordates have the following features at some point in their life (in the case of humans and many other vertebrates, these features may only be present in the embryo): \n\n\npharyngeal slits - a series of openings that connect the inside of the throat to the outside of the "neck". These are often, but not always, used as gills.\ndorsal nerve cord - a bundle of nerve fibers which runs down the "back". It connects the brain with the lateral muscles and other organs.\n\nnotochord - cartilaginous rod running underneath, and supporting, the nerve cord.\n\npost-anal tail - an extension of the body past the anal opening.
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Umm...I've been making jokes about larval humans for years, so I had to laugh. Bugs have larval stages, but vertebrates don't. The larval stage is the maggot stage. In humans, some people refer to that as "middle school"...but that's only when we look back as adults. Kids these days have evolved and aren't nearly so maggoty as we once were ;)
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One of the most significant changes that occurred in early vertebrate evolution is that of the development of jaws.  Jaws first appeared generally in gnathostomes, but more specifically in shark like ancestors called placoderms. Present day sharks are the representative group of early vertebrates with jaws. \n\nThere are two theories on why jaws first evolved. One theory ("new skull") states that jaws evolved to aid in more efficient feeding and feeding on larger prey, which increased metabolic rate and thus allowed for a more active lifestyle. The other theory, "new mouth", states that jaws evolved to allow for more efficient ventilation mechanisms, which allowed for a higher metabolic rate and thus a more active lifestyle. Secondarily in this scenario, jaws also aided in more efficient feeding.\n\nAlso, it should be noted that many animal groups that evolved prior to the early vertebrates has pharyngeal slits or pharyngeal openings. That isn't really a characteristic specific to vertebrates as several pre-chordate and chordate groups have pharyngeal/gill slits.
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lizards = frogs\nfrogs = lizards
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Wow, 5 people responded before me and never really answered your question.\n\nThe main question you asked was about "complex animals" compared to land plants. You were understanding this right.  Remember that those early plants were more similar to modern bryophytes (like mosses, liverworts and hornworts).  The vertebrates at that time were all sea creatures (very primitive fish-like).\n\nBy the time the land vertebrates appeared, large trees were abundant and so were insects.\n\nAlso, why do some people insist on using a book that says insects have 4 legs and calls bats birds as their science book?
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http://biodidac.bio.uottawa.ca/thumbnails/catquery.htm?Kingdom=Animalia&Phylum=Hemichordata&category=photo
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Many organisms possess vestigial structures that have no apparent function, but that resemble structures their presumed ancestors had. Humans, for example, possess a complete set of muscles for wiggling their ears, just as a coyote does (table 22.1). \n\nBoa constrictors have hip bones and rudimentary hind legs. Manatees (a type of aquatic mammal often referred to as "sea cows") have fingernails on their fins (which evolved from legs). Figure 22.17 illustrates the skeleton of a baleen whale, which contains pelvic bones, as other mammal skeletons do, even though such bones serve no known function in the whale. The human vermiform appendix is apparently vestigial; it represents the degenerate terminal part of the cecum, the blind pouch or sac in which the large intestine begins. In other mammals such as mice, the cecum is the largest part of the large intestine and functions in storageusually of bulk cellulose in herbivores. Although some suggestions have been made, it is difficult to assign any current function to the vermiform appendix. In many respects, it is a dangerous organ: quite often it becomes infected, leading to an inflammation called appendicitis; without surgical removal, the appendix may burst, allowing the contents of the gut to come in contact with the lining of the body cavity, a potentially fatal event.\n    \nThe skeleton of a baleen whale, a representative of the group of mammals that contains the largest living species, contains pelvic bones. These bones resemble those of other mammals, but are only weakly developed in the whale and have no apparent function.\n    \nIt is difficult to understand vestigial structures such as these as anything other than evolutionary relicts, holdovers from the evolutionary past. They argue strongly for the common ancestry of the members of the groups that share them, regardless of how different they have subsequently become. \nComparisons of the anatomy of different living animals often reveal evidence of shared ancestry. In some instances, the same organ has evolved to carry out different functions, in others, an organ loses its function altogether. Sometimes, different organs evolve in similar ways when exposed to the same selective pressures.