are there any organisms that only have RNA? If so what are some examples?
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Not viruses in general but retroviruses.
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Bacteria appeared on earth between 3.4 and 4 billion years ago. Precambrian evidence of filamentous bacteria-like structures, found making up fossilized sediments called stromalites, has been discovered in Australia and southern Africa. These fossils date back between 3.4 and 3.5 billion years old. Environmental conditions of earth 4 billion years ago were much different than those of today. It has been theorized that the atmosphere was a reducing atmosphere with intense lightning, tremendous volcanic activity, very little oxygen, intense ultraviolet radiation, and meteorite bombardment. These conditions made it impossible for any type of aerobic life to exist. The first cells may have originated by chemical evolution in an anaerobic environment.\n\nAbiotic Synthesis Theory of Life: A.I.Oparin postulated, in the 1920's, that primitive earth with its reducing atmosphere favored chemical reactions that produced simple monomers that eventually formed complex organic compounds necessary for life. Stanley Miller and Harold Urey tested this hypothesis by building an apparatus to simulate the conditions of the earth at that time.\nTheir experiments produced 20 amino acids and other organic compounds including: ATP, lipids, some sugars, and the bases of RNA and DNA. The main problem of organic synthesis is how did these molecules develop without the aid of enzymes to speed up the reactions? Sidney Fox, of the University of Miami, dripped a dilute solution of organic monomers onto hot sand, clay , and rock. The water vaporized and left behind polypeptides he called proteinoids. Clay was abundant in prebiotic earth. Clay has the ability to act as a substrate for this type of chemical reaction. The charged sites on the clay attracted monomers in such concentrations to bring them into close proximity for chemical binding. Once these organic compounds were produced, aggregates of these proteinoids self-assembled into small spheres called protobionts. These small spheres were capable of osmotic swelling and shrinking and even able to produce a membrane potential.\n\nRNA the first Genetic Material: Evidence to support the idea that RNA was the first genetic material includes: short polymers of self-replicating RNA have been abiotically produced in a test tube without enzymes. RNA has the ability to act as a catalyst to help make mRNA, tRNA or rRNA. The RNA folding is unique depending on its sequence. This along with mutations, creates a variety of closely related molecules. Through chance this self-replicating material was captured by the protobionts and the entire structure developed under the guide of natural selection.\n\nOther Origin Theories:\n\nPanspermia. Extraterrestrial organic compounds located on the surface of meteorites could well have contributed to the pool of material found on prebiotic earth. Modern meteorites have given up specimens of simple organic compounds such as amino acids.\n\nSome researchers believe that life began on the sea floor away from the harsh surface environments. The discovery of deep sea vents showed the scientific community that the materials needed for life to begin were present away from the harsh surface.\n\nJulius Rebek produced a simple organic molecule in 1991 that served as a template for self-replication. This discovery suggests that RNA was too complex to have come first and a much simpler self-replicating molecule preceded it.
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B) RNA is found only inside the nucleus, whereas DNA is found only outside the nucleus.\n\nIn order for the statement to be true, the subjects (RNA & DNA) should be switched.
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Nucleic acids were discovered in 1869 by Johann Friedrich Miescher (1844-1895), who called the material 'nuclein' since it was found in the nucleus. It was later discovered that prokaryotic cells, which do not have a nucleus, also contain nucleic acids
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scientists have discovered a few life forms on earth that do survive without oxygen and water.\n\nhowever these are not as abundant as water/oxygen based life forms. \n\nearly life on earth might have started with methane/ammonia/some chemical other than water/oxygen.\n\nthis life might have been "slower" to grow move etc.\n\nOxygen helps to build faster/more efficient organisms.\n\nthe search for life, or search that is like -- needle in a haystack or some grain of sand on the beach --- is a game of probabilities. \n\nsearchers try to increase their probabilities by adding more creteria.\n\nresources are limited....however the potential candidates are in trillions of trillions.\n\nFor example search for oil under the ground...you try to increase your chances of success by adding creteria from knowledge you have accumulated over the years.\n\nwe think the probabilities of life are higher where there is water.\n\nits all about working with probabilities when the resources are very limited and you are trying to reduce the number of potential "candidates" that are in trillions of trillions.\n\nexistance of water also means that the temperature,  pressure and some of the other environment conditions are more hospitable to life (on that place/planet) as we know it.
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One good one:\n\nDNA replication is much more resistant to errors ... so DNA molecules can be *much* longer than RNA and still survive replication.  This supports the stable propagation of a much larger number of genes (tens of thousands of genes) from generation to generation without degradation.
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Moneran - Includes bacteria, blue green algae, and primative pathogens.  Considered the most primative kingdom, it represents prokaryotic life forms - they have no distinct nuclei\n\nProtista - simples eukaryotes.  Include protozoa, unicellular and multicellular algae, and slime mold.  Ancestor organisms to plants, animals, fungi; most can move around by means to flagella\n\nFungi - includes mushroom, bread molds, and yeasts.  Fungi lack the ability to photosynthesize, so they are called decomposers, breaking down and feeding on dead protoplasm.\n\nPlantae - have the ability to photosynthesize, so they are called producers.  They are two major phyla, Bryophyta, or mosses and Tracheophyta - which have vascular systems and include most of the plants you know.\n\nAnimalia - produce energy by consumering other organisms, so they are called consumers.  Can be either vertebrates, phylum Chordata, or invertebrates such as mollusks, arthopods, sponges, coelenterates, worms, etc.
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Question 1:\n5 Kingdoms- Monera, Protista, Fungi, Plantae, Animalia\nMonera:  are single-celled organisms with no organelles or cell nucleus. Often have cell wall in addition to cell membrane.  (includes all forms of bacteria)\nProtista: single-celled, have organelles and nucleus.  Include yeast.\nFungi: Multicellular, have organelles and nucleus, some go through photosynthesis and produce their own food, while others don't.  (includes mushrooms, bread mold, moss)\nPlantae:  Multicellular, organelles present, nucleated, undergo photosynthesis/so they have chloroplasts (includes all plants)\nAnimalia: multicellular, organelles, nucleated, cannot produce their own food, do not undergo photosynthesis.(animals)\n\nQuestion 2.  SOme say there are 6 kingdoms because Kingdom Monera is divided into Eubacteria and Archaebacteria.  Archaebacteria were the first organisms on the planet, and live under harsh conditions (volcanic hot spots underwater, etc).  Eubacteria are different in structure and are present in friendlier conditions (your bathroom floor, toilet, your intestines, etc)\nScientists do this to separate the two different types of bacteria...although most modern books have them all under Monerans
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Any life form as we know it could never live on Uranus. Of course, I think it's a bit arrogant and short-sighted to think that we know any and all forms that life can take. After all, life exists at the bottom of oceans where it was once thought living organisms could never survive. We have such a small perspective so far that there could be many forms of life that we can't currently imagine. Only time will tell.
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i gave u a website on ur previous answer that can answer ur question of RNa\nand the seqence is called TRNA   fits in the protein of ribosome
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Well the answer is all of the above, which is wrong.\n\nBoth single stranded and double stranded RNA molecules exist.   Single stranded and double stranded DNA both exist as well.\n\nThough in both cases, the less common variant (dsRNA and ssDNA) is usually viral.
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Amoeba are among the largest single celled organisms, far larger than any bacteria.  Some amoeba are large enough to be seen without needing a microscope!\n\nBacteria are the smallest living things and mycoplasms are the smallest living bacteria (known as nanobacteria).\n\nIf by creatures you mean animals, then the smallest depends a bit on your definition of "small".  The shortest is probably little Trichoplax adhaerens, which looks a bit like a hairy, multi-cellular amoeba.\n\nThe smallest animal in terms of number of cells is probably some kind of Mesozoa, a set of worms famous for being very short and only a few cells across, so much thinner than Tricoplax and less massive.\n\nThe smallest vertebrate is a species of fish that was just discovered recently, though I forget the name of it, sorry.  :-)\n\nIt's recently been discovered that a few single-celled organisms are, in fact, evolved from animals.  If you would count these as animals, they would be the smallest animals, though that would be merely a technicality.\n\nAll of this applies only to adult forms, of course.  We're all very very small to begin with!
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1.\n\n\n\n\n\n\n2. Viruses are neither unicellular nor multicellular organisms; they are somewhere between being living and non-living. Viruses have genes and show inheritance, but are reliant on host cells to produce new generations of viruses. Many viruses have similarities to complex molecules. Because viruses are dependent on host cells for their replication they are generally not classified as "living". Whether they are "alive", they are obligate parasites, and have no form which can reproduce independently of their host. Like most parasites, they have a specific host range, sometimes specific to one species (or even limited cell types of one species) and sometimes more general.\n\n3. protozoa and algae. I don't know why\n\n4. The protozoa are mostly single-celled, motile, and feed by phagocytosis, though there are numerous exceptions. They are usually only 0.01-0.5 mm in size, generally too small to be seen without a microscope. They are ubiquitous throughout aqueous environments and the soil, commonly surviving dry periods as cysts or spores, and include several important parasites. Based on locomotion, protozoa are grouped into:\n\nFlagellates with long flagella  -like Euglena\nAmoeboids with transient pseudopodia   -like Amoeba\nCiliates with multiple, short cilia    -Paramecium\nSporozoa non-motile parasites; form spores like Plasmodium.\n\n\n\n5. The algae gather light energy through photosynthesis. They include many single-celled creatures that are also considered protozoa, such as Euglena and Paramecium bursaria, which have acquired chloroplasts through secondary endosymbiosis. Others are non-motile, and some are truly multicellular, including some members of the following groups:\nChlorophytes green algae, related to higher plants  -like Ulva\nRhodophytes red algae  -like Porphyra\nHeterokontophytes brown algae, diatoms, etc.  -like Macrocystis\n\nThe green and red algae, along with a small group called the glaucophytes, appear to be close relatives of other plants, and so some authors treat them as Plantae despite their simple organization. Most other types of algae, however, developed separately. They include the haptophytes, cryptomonads, dinoflagellates, euglenids, and chlorarachniophytes, all of which have also been considered protozoans.\n\n\n6.\n\n\n\n\n\n\n7.\n\n\n\n\n\n\n8. hyphae is any of the threadlike filaments forming the mycelium of a fungus. Hyphae is a long, branching filament that, with other hyphae, forms the feeding thallus of a fungus called the mycelium. Hyphae are also found enveloping the gonidia in lichens, making up a large part of their structure. A typical hypha consists of a tubular wall, usually made of chitin, which surrounds, supports, and protects the cells that compose a hypha. For most fungi, a cell within a hyphal filament is separated from other cells by internal cross-walls called septa (singular septum).\n\nSome forms of parasitic fungi have a portion of their hyphae modified to form haustoria that are able to penetrate the tissues of a host organism. Similar, yet mutualistic forms of penetrating hyphae are called mycorrhizae and are important in assisting nutrient and water absorption by plants.\n\n\n\n9. \n\n\n\n\n\n\n\n\n10. Lichen is a fungus, usually of the class Ascomycetes, that grows symbiotically with algae, resulting in a composite organism that characteristically forms a crustlike or branching growth on rocks or tree trunks.
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The answer to your question is (C). \n\nEvery living organism is made up of one or more cells, all cells arise from preexisting cells, the smallest living organisms are single cells, and cells are the functional units of multicellular organisms.\n\n"Virus - a non cellular parasitic particle that consists of a protein coat surrounding a strand of genetic material; multiplies only within a cell of a living organism (the host)."
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well...\nu could talk about how little we know about whether organisms like bacteria and viruses have consicousness and a probable effect that might happen if we change their genomes . we dont really know whether those kind of organisms have an "individuality" or anything, so thats where i would start off from.\nhope this helped
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one celled organism are organism which consists of only one cell.examples are Amoeba,euglena and paramecium while  many-celled organism or muticellular organisms consists of two or more cells.Examples are man,bird,hydra,flowering plants,volvox ,hydra and fish
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A biomolecule is a chemical compound that naturally occurs in living organisms. Biomolecules consist primarily of carbon and hydrogen, along with nitrogen, oxygen, phosphorus and sulfur. Other elements sometimes are incorporated but these are much less common.\n\nBiomolecules are necessary for the existence of all known forms of life. For example, humans possess skin and hair. The main component of hair is keratin, an agglomeration of proteins which are themselves polymers built from amino acids. Amino acids are some of the most important building blocks used, in nature, to construct larger molecules. Another type of building block is the nucleotides, each of which consists of three components: either a purine or pyrimidine base, a pentose sugar and a phosphate group. These nucleotides, mainly, form the nucleic acids.\n\nBesides the polymeric biomolecules, numerous small organic molecules are absorbed or synthesised by living systems. Many biomolecules may be useful or important drugs.