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Decomposition
Topic 4: Decomposition
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1Introduction2Deep Dive3Deep Dive4Practical5Deep Dive6How It Works7Definitions8Misconceptions9Memory Aid10Exam Focus11Exam Tips12Summary
Nature's Recycling Team
What is Decomposition?
Conditions Affecting the Rate of Decomposition
Required Practical: Measuring Decomposition Rate
Composting and Biogas
Why Conditions Affect the Rate of Decomposition
Key Definitions
Common Misconceptions
Memory Aids
Exam Focus
Exam Tips for Decomposition
Knowledge Organiser
Sample Flashcards
What is decomposition and who carries it out?
Decomposition is the breakdown of dead organisms and waste into simpler substances.
Carried out by decomposers: mainly bacteria and fungi.
This releases nutrients back into the soil for plants to use.
How do decomposers feed? (saprotrophic nutrition)
Decomposers use saprotrophic nutrition:
1. Secrete enzymes onto dead material (extracellular digestion)
2. Enzymes break down large molecules
3. Decomposer absorbs the small soluble products
Exam questions for Decomposition
Which organisms are the main decomposers?
Explain how temperature affects the rate of decomposition.
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