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| | Multicellular stage, Animals |
 | | Multicellular animals direct behavior at other objects by the contraction of muscle cells located where the muscles are needed to change the body’s shape, and neurons generate behavior by controlling the relevant muscles. | | | After constructing the queen’s body, her body is used to construct the other members, and the queen becomes the center of a multisomatic structure in which pheromones are used to coordinate the behavior of her multicellular offspring (the same mechanism used to coordinate cells at the multicellular level). | | | Thus, the organism's behavior as a whole depends mainly on the biological behavior guidance system at the multicellular level, and it reproduces as a whole. |
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http://www.twow.net/ObjText/OtkCbGeRRS04B.htm
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| | From Single Cells to Multicellular Organisms 18 |
| | During evolution many of the developmental devices that evolved in the simplest multicellular organisms have been conserved as basic principles for the construction of their more complex descendants. | | | This principle, applying at first to simple associations of cells, has been taken to an extreme in the multicellular organisms we see today. | | | Innovations in movement, sensory detection, communication, social organization - all enabled eucaryotic organisms to compete, propagate, and survive in ever more complex ways. |
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http://www.ncbi.nlm.nih.gov/books/bv.fcgi?db=Books&rid=cell.section.61
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| | Gould: The Evolution of Life on the Earth |
| | These thin, quilted, sheetlike organisms may be ancestral to some modern forms but may also represent a separate and ultimately failed experiment in multicellular life. | | | If complexity is such a good thing, and multicellularity represents its initial phase in our usual view, then life certainly took its time in making this crucial step. | | | Humans arose, rather, as a fortuitous and contingent outcome of thousands of linked events, any one of which could have occurred differently and sent history on an alternative pathway that would not have led to consciousness. |
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http://www.brembs.net/gould.html
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| | Multicellular Organisms |
| | The more complex multicellular organisms cope with the problem of being vulnerable to changes in the environment by surrounding their individual cells with fluid that is separated from the environment by a barrier such as the skin. | | | By maintaining the internal environment constant, multicellular organisms are less vulnerable to changes in the external environment. | | | This is the reason multicellular organisms have developed transport systems such as the circulatory system. |
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http://www3.fhs.usyd.edu.au/bio/homeostasis/Multicell_organisms.htm
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| | Kota Miura |
| | Multicellular movement is also reachable with current microscopic techniques. | | | A large body of results suggest that cyclic AMP-mediated cell-cell signaling is the mechanism coordinating multicellular movement. | | | Multicellular organism behaves as a single organism because cells within the organism move in a coordinated manner. |
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http://www.embl-heidelberg.de/~miura/res_projectMulticellularBio.html
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| | Natural History: All for one and one for all: multicellular organisms have arisen more than once, each time through an ... |
| | And by studying how multicellular creatures such as volvox took that step, scientists can gather clues about how our own bodies evolved. | | | Of course, pathways need to be kept open to ensure that the individual cells are bathed in the necessary fluids. | | | Because multicellularity is an experiment that's been run many times in the history of life, scientists may be able to discover some universal rules for how it comes about. |
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http://www.findarticles.com/p/articles/mi_m1134/is_1_111/ai_82803329
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| | A new theory of the evolution of cooperation |
| | The mechanisms do not disclose a general method for organising cooperation amongst self-interested components that would work for any living processes in any circumstances. | | | But as a theory, kin selection has been very successful. | | | Multicellular organisms had to introduce additional controls to prevent mitochondria competing within them and undermining cooperation. |
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http://users.tpg.com.au/users/jes999/5.htm
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| | Idle Theory: Multicellular Life |
| | It may be asked how it is, if there is such a constant need for life to organize itself first into complex multicellulars, and then into societies of multicellulars, that there are any unicellular forms of life still extant? | | | Every human being carries many different species of them, living off discarded skin, or within the intestinal tract. | | | This is that it has been argued that multicellulars are more idle than unicellulars, and that life tends to be difficult for unicellulars. |
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http://www.idlex.freeserve.co.uk/idle/evolution/idlev2a/idlev-2a.html
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| | Evolution of Plants Lecture |
| | This involves an alternation between a multicellular diploid sporophyte which, through meiosis produces haploid spores which in turn undergo mitosis to form a multicellular gametophyte which makes, what else, gametes. | | | Plants are multicellular photosynthetic organisms that are believed to have | | | The multicellular diploid embryo is housed within a multicellular gametophyte (in algae the embryo is separate from the haploid tissue). |
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http://home.earthlink.net/~dayvdanls/PlantEvol.html
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| | United States Patent Application: 0040092471 |
| | As mentioned above, a critical feature of the subject methods is that the vector or vectors comprising the various elements of the Sleeping Beauty transposon system, e.g. | | | The method according to claim 1, wherein said multicellular organism is a vertebrate. | | | The method according to claim 12, wherein said multicellular organism is a vertebrate animal. |
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http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=/netahtml/PTO/srchnum.html&r=1&f=G&l=50&s1="20040092471".PGNR.&OS=DN/20040092471&RS=DN/20040092471
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| | Introductory Biology Courseware (111)- Protista |
| | Biologists are unsure whether ediacaran fauna represent early representatives of those two phyla or a lineage which left no living descendents (the basic body plans are considerably different from extant forms). | | | There are a diversity of forms of chlorophytes, with some being simple uni- or multicellular sessile forms, some being motile, and some being colonial or large multicellular forms. | | | Either the haploid organism, the diploid organism, or both may also reproduce |
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http://tidepool.st.usm.edu/crswr/111protists.html
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| | The Social Superorganism and its Global Brain |
| | The fact that complex organisms, like our own bodies, are built up from individual cells, led to the concept of superorganism. | | | Society can be viewed as a multicellular organism, with individuals in the role of the cells. | | | If cells aggregate to form a multicellular organism, then organisms might aggregate to form an organism of organisms: a superorganism. |
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http://pespmc1.vub.ac.be/suporgli.html
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| | Protoctista |
| | In the last two decades, however, the basis for classifying single-celled organisms separately from multicellular ones has weakened. | | | It has become evident that multicellularity evolved many times from unicellular forms - many multicellular organisms are far more closely related to certain unicells than they are to any other multicellular organisms. | | | For example, the ciliates, which are unicellular microbes, include at least one species that forms a sorocarp, a multicellular spore-bearing structure; euglenoids, chrysophytes, and diatoms also have multicellular derivatives. |
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http://www.bio.umass.edu/biology/conn.river/protoc.html
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| | Multi-cell Organisms |
| | This evolutionary development seems to indicate that earlier life tried to construct the multicellular body from the simpler cell unit in haploid state. | | | Multicellular organism development involves many processes as illustrated in the simple case of slime moulds. | | | The result is that all multicellular organisms, from small algae and fungi to elephants and human, have a unicellular stage and a large stage of varying dimensions in their life cycle. |
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http://universe-review.ca/F10-multicell.htm
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| | Stephen Jay Gould, "Planet of the Bacteria" 1996 |
| | The first multicellular creatures—marine algae—enter the stage soon afterward, but these organisms bear no genealogical relationship to our primary interest: the history of animal life. | | | Oxygen, the most essential constituent of the atmosphere for human needs, now maintains itself primarily through release by multicellular plants in the process of photosynthesis. | | | The Earth's original atmosphere apparently contained little or no free oxygen, and this otherwise unlikely element both arose historically and is now maintained by the action of organisms. |
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http://www.stephenjaygould.org/library/gould_bacteria.html
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| | phyto1 |
| | So understanding the relationship between the two generations is important in the study of plant development. | | | Aside from the difference in ploidy level between the gametophyte and sporophyte, there may be some interesting parallels to draw with metamorphosis in insects and amphibians. | | | Unlike animals, plants have multicellular haploid and multicellular diploid stages in their life cycle. |
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http://zygote.swarthmore.edu/phyto1.html
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| | A-signal production in Myxococcus xanthus |
| | This change from a vegetative to developmental cycle involves many cell-cell interactions, and a putative developmental pathway exists, though not thoroughly understood. | | | Further molecular and genetic studies will undoubtedly hasten the explanation of this fascinating phenomenon, as they are an excellent opportunity to explore some of the most primitive examples of multicellularity in a prokaryotic system - where the power of molecular and genetic experiments is greatest. | | | Myxococcus xanthus, a gram-negative bacterium found usually in soil, is one of the most well characterized of the myxobacteria with respect to regulation of gene expression during development. |
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http://www.ucs.mun.ca/~barretta/homepage.html
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| | Multicellular Parasites |
| | They live in a large variety of tissues, though many are specialized to single tissues such as muscle, vein, brain, or intestine. | | | Helminths are eucaryotic, multicellular animals that are mostly parasitic of other animals. | | | Usually a parasite is considered to be something smaller than the host and therefore capable of parasitizing only one host at a time. |
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http://www.mansfield.ohio-state.edu/~sabedon/biol3050.htm
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| | INSIDE ANCIENT ANIMAL EMBRYOS AND ALGAE — COMPUTED TOMOGRAPHIC ANALYSIS OF NEOPROTEROZOIC MULTICELLULAR EUKARYOTES |
| | Previous work on these fossils has been limited to examination of their three-dimensional external morphology using SEM or their two-dimensional internal morphology using thin-section observation. | | | 600 Ma Doushantuo Formation provide critical information about the evolution of early multicellular organisms and exhibit spectacular cellular-level preservation. | | | All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions. |
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http://gsa.confex.com/gsa/2002AM/finalprogram/abstract_39474.htm
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| | Multicellular organisms |
| | "The path from a unicellular condition to a multicellular one has been well-traveled. | | | Somehow the germ cells exchange proliferation by fission within the organism for reproduction by seed across generations, and the specialized somatic cells gain in reproductive opportunities by fission within the organism. | | | The path from multicellularity to cellular differentiation, however, proved a far less porous filter. |
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http://pespmc1.vub.ac.be/MULTICEL.html
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| | Multicellular organism - Wikipedia, the free encyclopedia |
| | Multicellular organisms must solve the problem of regenerating the whole from germ cells (i.e. | | | Multicellular organisms can suffer from cancer when cells fail to regulate their growth within the normal program of development. | | | Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. |
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http://www.wikipedia.org/wiki/Multicellular
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| | UCMP Glossary: Life history |
| | The sporophyte is multicellular and develops from a zygote. | | | haploid-diploid life cycle -- Occurs when a multicellular diploid phase, or sporophyte, alternates with a multicellular haploid phase, or gametophyte. | | | development -- The process by which a multicellular organism is produced from a single cell. |
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http://www.ucmp.berkeley.edu/glossary/gloss6lifehist.html
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| | Multicellular Organization Laboratory |
| | @@@@How the shape and behavior of multicellular organisms are determined by genetic information is one of the most fundamental problems in biology. |
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http://www.nig.ac.jp/labs/MultiOrg/home1e.html
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| | Cells the Fundamental Unit of Life |
| | In multicellular organisms individual groups of cells have become specialised to perform particular roles in the life of the organism. | | | In simple multicellular organisms such as sponges all the cells are very similar, in more complicated multicellular organisms the degree of specialisation of cells is much greater resulting in cells that are very different from one another. | | | The life of the organism is dependant on the correct working of all the different groups, each of which is dependant on all the others for its continued existence. |
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http://www.earthlife.net/cells.html
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| | IFI U.S. Class Hierarchies |
| | The nonhuman animal is a model for human disease 800-010.000. | | | The nonhuman animal is a model for human disease 800-011.000. | | | The nonhuman animal is a model for human disease 800-012.000. |
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http://www.ificlaims.com/IFICLS/uch/800.htm
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| | ALGAE AND FUNGUSLIKE PROTISTS |
| | Although most species of algae are unicellular, some are large, multicellular organisms. | | | Algae differ from protozoa, which are also classified in the Kingdom Protista, in that they manufacture their food through the process of photosynthesis. | | | FOUR Types of Algae are recognized, based on the following Body Structures: UNICELLULAR, COLONIAL, FILAMENTOUS, AND MULTICELLULAR. |
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http://www.sirinet.net/~jgjohnso/algae.html
(3053 words)
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| | Animal Phyla |
| | Multicellular animals are heterotrophic by ingestion of food into a body cavity (coelom) that is completely lined by the mesoderm. | | | Multicellular animals have three variations in the site of embryo development and source of nutrition. | | | Sexual reproduction may involve monoecious species in which members of the population are bisexual (hermaphroditic) with sperm-bearing testicles and egg-bearing ovaries on the same individual. |
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http://waynesword.palomar.edu/trnov01.htm
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| | Multicellular |
| | Any organism which is composed of many cells is termed multicellular. |
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http://www.cartage.org.lb/en/themes/Reference/dictionary/cellular/M/Multicellular.html
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| | Kingdom Protista |
| | Most are unicellular, some are colonial, and other are simple multicellular organisms closely related to single protist cells. | | | The ciliates are primarily free-living protozoans who move by means of numerous cilia, and contain two different types of nuclei: a large macronucleus that controls cell metabolism and development, and many smaller micronuclei that function in sexual reproduction. | | | When sufficient bacteria (food) are present, cellular slime molds are single amoeboid cells; however, when food becomes scarce, they aggregate into sluglike colonies, which become large reproductive structures. |
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http://sidwell.edu/us/science/vlb5/Labs/Classification_Lab/Eukarya/Protista
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| | BioMed Central Full text A molecular timescale of eukaryote evolution and the rise of complex multicellular life |
| | The results suggest that oxygen levels in the environment, and the ability of eukaryotes to extract energy from oxygen, as well as produce oxygen, were key factors in the rise of complex multicellular life. | | | The results support a deep history for complex multicellular eukaryotes, and implicate oxygen as a possible trigger for the rise in complex life. | | | The pattern and timing of the rise in complex multicellular life during Earth's history has not been established. |
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http://www.biomedcentral.com/1471-2148/4/2
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| | Size and Shape in Diatoms |
| | Depending on their mode of construction, colonies may be flexible, or rigid. | | | Although individual cells are most commonly in the size range of 10 - 200 µm, many planktonic diatoms form multicellular chains which can be several millimeters in length, occasionally exceeding a centimeter. | | | The silicified cell wall allows them to exhibit a multitude of complex, often highly geometric shapes at both the cellular and colonial levels. |
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http://thalassa.gso.uri.edu/ESphyto/sizeshap/shape.htm
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