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Organism-Supporting cycles
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The Nitrogen Cycle -The Nitrogen Cycle represents one of the most important nutrient cycles found in ecosystems. Nitrogen is necessary for all living cells. -Nitrogen is used by living organisms to produce a number of complex organic molecules like amino acids, proteins, and nucleic acids. -As you know, about 78% of our Atmosphere is Nitrogen gas. Other major stores of nitrogen include organic matter in soil and the oceans.
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The process of converting nitrogen is called Fixation.
B u t W a i t ! Take a deep breath.... Most of what you just inhaled is nitrogen. Your body does not use the nitrogen that you inhale with each breath. But, like all living things, your body needs lots of nitrogen. Your body gets the nitrogen it needs to grow from food. Because of the fact that Nitrogen gas in the atmosphere is almost entirely unusable to life forms, It must first be converted or “fixed” into a more usable form. Did You Know?? The process of converting nitrogen is called Fixation. N2 + 8H+ + 8e ATP = 2NH3 + H2 + 16ADP + 16 Pi After nitrogen is fixed, it can be absorbed, and used by plants, and subsequently by animals. The process of nitrogen being fixed, used by plants and animals, and later returned to the atmosphere is referred to as the nitrogen cycle.
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IN OTHER WORDS Precipitation brings down nitrogen from the atmosphere where nitrogen-fixing bacteria found in the soils convert free nitrogen into substances that other organisms can use. When the fixing process is finished, free nitrogen is converted into nitrates, nitrites, and ammonia. These substances can be used by plants. As the plants become food, the nitrogen can be used by animals! As part of the cycle, animals eat plants containing usable nitrogen, and thus return it as organic material (animal waste, decaying plants and animals) to be decomposed by bacteria and other decomposers. Decomposers (fungi, bacteria, worms, etc.) convert the nitrogen found in other organisms into ammonia and return it to the soil – “freeing up” nutrients. A few of these type of bacteria return nitrogen to the atmosphere too. Some Nitrogen (not much) is actually fixed by lightning in the atmosphere! Interesting Facts: Most fertilizers used by farmers (and others) to grow plants are primarily nitrates (fixed nitrogen)
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A “simple” description
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A bit more complex... Like all natural cycles, the Nitrogen Cycle depends on many other “cycles” to operate. How is the Water Cycle nessessary within this cycle?
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Photosynthesis is indeed a very complicated process....
Plants not only rely on energy from fixed nitrogen but also directly from the Sun. Photosynthesis is indeed a very complicated process.... Photosynthesis - The process by which plants, some bacteria, and some protista (algae) use the energy from sunlight to produce ATP, the "fuel" used by all living things. The green pigment protein in plants and other such oraganisms is known as Clorophyll. This is found in the organelles called Chloroplasts in a plant cell. This process produces two things animals like us like – Oxygen and Food! 6H2O + 6CO > C6H12O6+ 6O2
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I can make my own food using only CO2 and sunlight
I can make my own food using only CO2 and sunlight! I am a photo – autotroph y’all... THE BOTTOM LINE Plants use the sun’s radiation to convert carbon dioxide into organic compounds (mainly sugars) that both it, and those who eat it need for energy and survival in an ecosystem. I don’t see the “big deal” – poisonous gases being converted to what we need breathe and eat...who cares? …idiot
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The Carbon Cycle All living things are made of Carbon. Carbon is also a part of the ocean, air, and even rocks. Because the Earth is a dynamic place, carbon does not stay still. It is on the move! This is referred to as the Carbon Cycle. In the atmosphere, carbon is attached to some oxygen in a gas called carbon dioxide. As you know, plants use carbon dioxide and sunlight to make their own food and grow. The carbon becomes part of the plant. Anything that eats the plant, incorporates the carbon into itself!
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Every so often, a plant or animal does not decompose right away
Every so often, a plant or animal does not decompose right away. Their bodies are trapped, in locations where decomposition can simply not take place. This is most common at the bottom of oceans and seas, where the life forms become buried by sand. Instead of returning to the atmosphere, the carbon from these life forms is trapped within the Earth. Over millions of years more and more of the carbon on Earth has been trapped in this manner. Today, almost 99% of all the carbon on Earth has been “locked” up deep within the Earth. How exactly does the Carbon Cycle interact with the Rock Cycle?
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As rocks weather, this carbon is slowly released back into the atmosphere, creating a balance. For the past several hundred million years, the amount of carbon being locked up in the Earth, and the amount being released by weathering rocks was almost perfectly balanced. Plants that die and are buried may turn into fossil fuels made of carbon like coal and oil over millions of years. When humans burn fossil fuels, most of the carbon quickly enters the atmosphere as carbon dioxide. This important balance has been altered significantly in the past century, as humans have begun using fossil fuels to produce energy. By burning up the Earth’s store of carbon, humankind is able to create the energy needed to operate our communities. However, we must be careful as we do so. By releasing more carbon into the atmosphere than is being locked up, we risk causing damage to the delicate carbon cycle.
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What’s going on....
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Why does energy decrease as it moves “up” the pyramid?
Think of how each cycle and process is involved in a simple Energy Pyramid... Why does energy decrease as it moves “up” the pyramid?
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