1. What is Nitrogen? N makes up about 78% of our atmosphere. N in the atmosphere it is mostly in the form of ______, which is a compound that plants and animals cannot use. The process of converting N into compounds that can be used by plants and animals is called the ______________________. N2N2 Nitrogen Cycle
2. Why we care about nitrogen… N is an essential component of _____________________. The building blocks of life. DNA, RNA and Proteins
3. How does atmospheric N (N 2 ) get changed into a form that can be used by most living organisms? The Nitrogen Cycle (it must be ‘fixed’)! Nitrogen Cycle (1) Nitrogen Fixation (2) Ammonification (3) Nitrification (4) Denitrification
4. Nitrogen Fixation ___________________ is the process in which the N 2 compound in the atmosphere breaks and combines with other compounds. The N is _________ when it combines with ______________ or _______________. N N H N HH N2N2 Nitrogen Fixation “fixed” hydrogenoxygen Ammonia (NH 3 ) Nitrous Oxide (N 2 O)
Check for Understanding What is ‘unusable’ nitrogen called? What must happen to it before it is available for life? What two elements are added to N during fixation?
5. Three ways to “fix” N Main process: Special ____________ convert the N gas (N 2 ) to ammonia (NH 3 ), which only ________ plants can use (peas, beans). _________________ strikes convert N 2 to N 2 O or NO 3. Industrial production. ____________ manipulation turns N 2 into NH 3 (Fertilizer) bacteria some Lightning Chemical
6. Ammonification _____________________ - After all the living organisms have used the ___________________, decomposer bacteria convert the N to _______________. N H H H Ammonification organic nitrogen ammonia Bacteria Ammonia Organic Nitrogen (proteins)
7. Nitrification _______________ is the process that converts ammonia (NH 3 ) into nitrites (NO 2 ) and nitrates (NO 3 ) which ____ plants _______ use. Note: Ammonia comes from ______ N fixation and ammonification 8. How is it done? _____________________ N N N H H H O O O OO Nitrification most can Both Bacteria!
9. Denitrification _______________: Process in which N compounds _____________________ into atmospheric N (N 2 or N 2 O). The main process is performed by _____________________ in the soil. It can also happen by _____________ fossil fuels. N2ON2O NO 3 N2N2 Denitrification convert back bacteria burning
Check for Understanding What are the 3 ways to fix N? What process converts ammonium or ammonia Into nitrates and/or nitrites? What process takes fixed N and returns it back to atmospheric N?