The Nitrogen Cycle
The nitrogen cycle: nitrogen-fixing, nitrifying, denitrifying bacteria, ammonification, and the role of legumes
What you'll cover
- Nitrogen gas in atmosphere (78%)
- Nitrogen-fixing bacteria (Rhizobium in root nodules)
- Nitrifying bacteria (ammonia to nitrates)
- Denitrifying bacteria (nitrates to nitrogen gas)
- Ammonification by decomposers
- Plants absorb nitrates via active transport
- Comparison with carbon cycle
- Role of legumes in crop rotation
Study this topic
Why Do Farmers Add Fertiliser?
The Big Picture: Nitrogen's Journey
The Nitrogen Cycle Step by Step
The Nitrogen Cycle — Tap or Play to Explore
How It Works: Why Bacteria Are Essential
Nitrogen Cycle vs Carbon Cycle
Key Definitions
Key Facts Table: The Four Types of Bacteria
Common Misconceptions
Memory Aids
Higher Eutrophication: When Too Much Nitrogen Is a Problem
Exam Focus
Exam Tips: The Nitrogen Cycle
Knowledge Organiser
Sample Flashcards
Exam questions for The Nitrogen Cycle
What percentage of the atmosphere is made up of nitrogen gas (N₂)?
Explain the difference between nitrifying bacteria and denitrifying bacteria, including the conditions in which each type thrives.
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exam-style questions
15
revision flashcards
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