What are nitrogenous wastes and why do we have them?
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Our body uses amino acids in many ways. When an amino acid is degraded (e.g. phenylalanine to acetyl CoA) ammonia (NH3) is released as a byproduct. Ammonia itself is highly toxic to the human body, however, so we incorporate it into the less toxic urea molecule. Urea has pretty much no other role other than being a nitrogenous waste, and is a component of urine.
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It means it won't decompose to become environment-friendly after it has been discarded. Many rubbish items can be burnt in an incinerator, but not plastic. More research is needed to find alternative products that can be disposed of in a way that does not add to the mountains of rubbish being buried in landfill sites.
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Fixation. Ammonification. Nitrification. Denitrification\n\nFixation-taking fairly inert N2 gas and converting it to, for example ammonia,-  this is done generally through nitrogen-fixing bacteria\n\nThe ammonification, in which ammonia (NH3) is converted to ammonium ion (NH4+)\n\nNitrification, in which the ammonium ion is converted to NO3 or NO4 and either used as an energy source or used to produce amino acids and other organic compounds\n\nDenitrification- reduction of nitrogen back to the inorganic N2 form-usually through bacterial respiration
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www.google.com  \n"info on nitrogen"
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http://en.wikipedia.org/wiki/Nitrification\n\nThe two important elements of the process are that it is the oxidation of nitrogen (there are other processes that involve the reduction of nitrogen) and that it is carried out by specific species of bacteria.
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Nitrogen Cycle, natural cyclic process in the course of which atmospheric nitrogen enters the soil and becomes part of living organisms, before returning to the atmosphere. Nitrogen, an essential part of the amino acids, is a basic element of life. It also makes up 79 per cent of the Earth's atmosphere, but gaseous nitrogen must be converted to a chemically usable form before it can be used by living organisms. This is accomplished through the nitrogen cycle, in which gaseous nitrogen is converted to ammonia or nitrates (salts of nitric acid). The high energies provided by lightning and cosmic radiation serve to combine atmospheric nitrogen and oxygen into nitrates, which are carried to the Earth's surface in precipitation. Nitrogen fixation, the biological process which accounts for the bulk of the nitrogen-conversion process, is accomplished by free-living, nitrogen-fixing bacteria; symbiotic bacteria living on the roots of plants (mostly legumes and alders); cyanobacteria; certain lichens; and epiphytes in tropical forests.\n\nNitrogen “fixed” as ammonia and nitrates is taken up directly by plants and incorporated in their tissues as plant proteins. The nitrogen then passes through the food chain from plants to herbivores to carnivores in the process known as the food web. When plants and animals die, the nitrogenous compounds are broken down by decomposing into ammonia, a process called ammonification. Some of this ammonia is taken up by plants; the rest is dissolved in water or held in the soil, where micro-organisms convert it into nitrates and nitrites in a process called nitrification. Nitrates may be stored in decomposing humus or leached from the soil and carried to streams and lakes. They may also be converted to free nitrogen through denitrification and returned to the atmosphere.\n\nIn natural systems, nitrogen lost by denitrification, leaching, erosion, and similar processes is replaced by fixation and other nitrogen sources. Human intrusion in the nitrogen cycle, however, can result in less nitrogen being cycled, or in an overload of the system. For example, the cultivation of croplands, harvesting of crops, and cutting of forests have all caused a steady decline of nitrogen in the soil. (Some of the losses on agricultural lands are replaced only by applying energy-expensive nitrogenous fertilizers manufactured by artificial fixation.) On the other hand, the leaching of nitrogen from overfertilized croplands, cutover forestland, and animal wastes and sewage has contributed to water pollution by adding too much nitrogen to aquatic ecosystems, resulting in reduced water quality and the stimulation of excessive algal growth. In addition, nitrogen dioxide poured into the atmosphere from vehicle exhausts and power plants breaks down to form ozone and reacts with other atmospheric pollutants to form photochemical smog.\n\n\nCarbon Cycle (ecology), in ecology, the cycle of carbon usage by which energy flows through the Earth's ecosystem. The basic cycle begins when photosynthesizing plants use carbon dioxide (CO2) found in the atmosphere or dissolved in water. Some of this carbon is incorporated in plant tissue as carbohydrates, fats, and protein; the rest is returned to the atmosphere or water by respiration. Carbon is thus passed on to herbivores that eat the plants and thereby use, rearrange, and degrade the carbon compounds. Much of it is given off as CO2 in respiration, as a by-product of metabolism, but some is stored in animal tissue and is passed on to carnivores feeding on the herbivores. Ultimately, all the carbon compounds are broken down by decomposition, and the carbon is released as CO2 to be used again by plants.\nOn a global scale the carbon cycle involves an exchange of CO2 between two great reservoirs: the atmosphere and the Earth's waters. Atmospheric CO2 enters water by diffusion across the air-water surface. If the CO2 concentration in the water is less than that in the atmosphe
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It's not nitrogen... It's hydrogen. They called my car the "Hindenburg" after it burst into flames when I pumped in a few pounds too many way back when in Lakehurst, New Jersey... Oh, the humanity!
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Litter.\n\nI know it is probably not as dangerous to our health as Air Water or Noise but it is such a simple thing for people to take control of.\n\nDrives me nuts to see someone just toss there garbage out the car window or to the gutter when they are walking. \n\nPigs.
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natual gas I think - that's what they use in crematoriums.
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Nitrogen runoff from farm fertilizers, sewage, and air pollution is one of the big causes of ocean dead zones. When the nitrogen flows to the sea, it acts as a fertilizer to plankton. The abundant plankton use up all the ocean's oxygen. \nMitigation: \nReducing the discharge of nitrogen to rivers by reducing runoff, using less fertilizer, reducing nitrogen emissions from cars and factories, treating sewage better.
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they functins as human kidneys they help in excreting out the nitrogenous waste materials out of the body
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I would guess nitrogen.
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We can recycle so that today's garbage could be tomorrow's stuff.\nDon't throw out - recycle!
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There are a few types of nuclear (or radioactive) waste:\n\nHigh-level waste (HLW) contains the fisson products and transuranic elements, this includes spent fuel rods (which can't be used due to buildup of poisons such as xenon and samarium) and processing waste.  \n\nLow-level waste (LLW) contains radioactive isotopes with very short half-lives, this waste includes things like clothing and office supplies from hospitals.  This material can be disposed of by combustion or burial.  \n\nTransuranic waste contains elements with higher atomic numbers than uranium, this material generally has a long half life.  \n\nFor more information on nuclear wastes, see:\nhttp://en.wikipedia.org/wiki/Radioactive_waste
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if you mean plant waste, it is compost and makes very \ngood soil conditioning.
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A. Condensation. One might say D. but this would be wrong because the vapour has first to condense into tiny droplets (in clouds) which then clump together to form rain or snow (precipitation).\n\nNote that the other answers are 'blinds'. Nitrogen fixation has nothing to do with the water cycle. Recycling refers to re-using waste material. They are put there to test whether you know absolutely nothing, have heard some words about it, understand a little or have a good grasp of the subject.\n\nIf the question were marked out of 2, I would give 2 marks to A., 1 mark to D., maybe half a mark to C. if I felt the rest of the answers in the paper showed promise and no marks to B.\n\nWhen you are doing tests, it very often helps to ask, "Why are they asking this question?", "What piece of knowledge are they testing?" and "Why these particular options?"
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It's a huge pit where cities take their garbage.  They line the pit with clay or plastic to stop toxic chemicals from leaking into the soil.  They run the garbage over with bulldozers to compress it as much as possible.  And when it is full (it usually takes years or decades to fill up), they cover it with plastic and then dirt and sometimes vegetation.  A landfill is a way to efficiently bury huge amounts of garbage without impacting the environment.