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Earth Science/Biology Standard 7a. Students know the carbon cycle of photosynthesis and respiration and the nitrogen cycle. What is nitrogen?. Chemical element N, atomic number=7 Colorless, odorless, tasteless, inert gas Makes up 78% of the atmosphere N 2 ,Dinitrogen gas, (Diatomic ) .
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Earth Science/Biology Standard 7a. Students know the carbon cycle of photosynthesis and respiration and the nitrogen cycle.
What is nitrogen? • Chemical element N, atomic number=7 • Colorless, odorless, tasteless, inert gas • Makes up 78% of the atmosphere • N2,Dinitrogen gas, (Diatomic )
Why is it important? Proteins and nucleic acids (DNA, RNA) in living organisms Nitrogen gas (N2)-> cannot be used directly. * Animals get nitrogen from plants or animals that ate plants
Forms of nitrogen Atmospheric Nitrogen: N2 Nitrate :NO3 Nitrite: NO2 Ammonia: NH4
What is the nitrogen cycle? The process by which nitrogen is converted between its chemical forms It can be carried out by both biological and non-biological processes Bacteria are key element of the cycle
Where does it go? • Microbes Microbes
Nitrogen fixationbreak apart N2 Atmospheric: lightning Biological: bacteria Industrial: great pressure and temperature
Atmospheric Nitrogen and Nitrogen Fixation Triple bond is very stable Nitrogen gas- ammonia Mainly through bacteria
Bacteria Single celled Very small, microscopic
Nitrogen fixing bacteria Bacteria living in root nodules of LEGUMES (soybeans, peanuts, alfalfa) Bacteria living in soil and water
Assimilation • Plants • Nitrate->nitrite-> ammonium-> amino acids, nucleic acids • Ammonium-> amino acids, nucleic acids (in legumes) • Animals eat plants amino acids, nucleotides
Mineralization (ammonification) • Plant or animal dies, animal excretes waste • Bacteria convert organic nitrogen to ammonium
Nitrification • Bacteria convert ammonium to nitrate • nitrite-> nitrate->ammonium • Nitrate-> ammonium • Can seep into groundwater • Health problems • Environmental problems
Denitrification • Bacteria convert Nitrate to Nitrogen gas • Completes the cycle by returning nitrogen to the atmosphere
Increased Nitrogen emissions • Cultivation of legumes • Artificial fixation of nitrogen • Nitrogen oxide from cars and factories (greenhouse gas, destroys ozone layer)
In water… • Acidification • Eutrophication Too much nitrogen in the water (mostly due to runoff from land) -> more algae (algal blooms) -> take up oxygen-> affects other organisms (animal lives die)
Earth Science/Biology Standards 7c. Students know the movement of matter among reservoirs is driven by Earth's internal and external sources of energy
What drives photosynthesis?(Carbon transfer: atmosphere->biomass)
What type of energy is produced during cellular respiration and *decomposition?
What powers subduction zones?Energy transfer between hot interior and cool exterior
Convectionmovement of molecules in liquids and gases, “flowing”
Coal Formation?Plants that died millions of years ago*Pressure by sedimentary rocks
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