lecture_notes_10_7_07

lecture_notes_10_7_07 - Lecture Notes 10-7-07 NITROGEN...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture Notes 10-7-07 NITROGEN CYCLE: 78% of the atmosphere is N 2 , but this gaseous form is not available to most organisms Plants need ammonium or nitrate; animals get N from organic matter Some N precipitates from the atmosphere Most steps in the cycle involve biota Fig. 54.17 Nitrogen Cycle Summary: 5 Steps 1. NITROGEN-FIXATION N 2 NH 3 (ammonia) Bacteria ( Rhizobium ) in nodules of roots of terrestrial legumes or cyanobacteria (blue- green algae) in aquatic systems. This process functions under conditions of low O 2 and involves the enzyme nitrogenase. Lightning
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2. NITRIFICATION – Conversion of NH 3 to nitrate NO 3 Aerobic soil bacteria 3 . ASSIMILATION ---Uptake of ammonium or nitrate and incorporation into organic compounds by plants and of N-containing organic compounds by animals eating plants and other animals 4. AMMONIFICATION – Conversion of N-containing organic compounds to ammonia Bacteria, Fungi 5. Denitrification – Conversion of nitrates to N 2 Anaerobic bacteria
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

lecture_notes_10_7_07 - Lecture Notes 10-7-07 NITROGEN...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online