Decomposition - Steps and Factors - Unsolved Practice Set
Chapter: Ecosystem | Topic: Decomposition Steps and Factors
DECOMPOSITION - STEPS AND FACTORS - UNSOLVED PRACTICE SET
Topic: Decomposition Steps and Factors
Multiple Choice Questions
Q1. Decomposition refers to the process by which:
- Producers synthesise organic matter through photosynthesis
- Complex organic matter is broken down into simpler inorganic substances
- Consumers capture and eat prey organisms
- Energy flows only in one direction through a food chain
Q2. The organic waste materials, such as dead plant and animal remains, that serve as the raw material for decomposition are collectively called:
- Humus
- Detritus
- Biomass
- Nutrients
Q3. The initial breakdown of detritus into smaller particles by detritivores (such as earthworms) is called:
- Leaching
- Fragmentation
- Humification
- Mineralisation
Q4. The final step of decomposition, in which humus is further broken down to release inorganic nutrients back into the soil, is called:
- Fragmentation
- Leaching
- Mineralisation
- Catabolism
Q5. Decomposition generally occurs at a faster rate under conditions of:
- Cold, dry climates
- Warm temperature and adequate moisture
- Extremely low humidity with no moisture
- Complete absence of oxygen only
Short Answer Questions
Q6. Define decomposition, and name the main organisms responsible for carrying it out.
Q7. What is detritus, and why is it considered the starting material for decomposition?
Q8. List the main steps involved in the process of decomposition, in order.
Q9. Name any two factors that can affect the rate of decomposition in an ecosystem.
Long Answer Questions
Q10. Describe the process of decomposition in detail, explaining each of its major steps - fragmentation, leaching, catabolism, humification, and mineralisation.
Q11. Discuss the factors that influence the rate of decomposition, explaining why decomposition occurs faster in some environments than in others.
APPLICATION / ANALYSIS
Q12. A gardener notices that fallen leaves and organic waste decompose much faster in a warm, moist compost pit compared to a similar pile of waste left out during a cold, dry winter. Explain, using your understanding of decomposition, why temperature and moisture affect the decomposition rate so significantly.
Q13. A biologist compares the decomposition rate of dead leaves rich in lignin (a tough, complex compound) with that of soft, nutrient-rich dead leaves from a different plant species. Predict which type of leaf litter would decompose more slowly, and explain your reasoning based on the chemical composition of detritus.