Cycles within Ecosystems Quiz
Studying this course? Keep your progress in one place.
Pick an answer for each. Quizzes never use energy.
5 questions, one answer each
Each answer is checked as you go, with why.
See all 5 questions
1. Which process removes carbon dioxide from the atmosphere?
- A. Respiration
- B. Combustion
- C. Photosynthesis
- D. Decomposition
2. What do nitrogen-fixing bacteria convert nitrogen gas into?
- A. Carbon dioxide
- B. Nitrogen compounds plants can use
- C. Oxygen gas
- D. Water vapour
3. Which bacteria convert nitrates back into nitrogen gas?
- A. Nitrifying bacteria
- B. Nitrogen-fixing bacteria
- C. Denitrifying bacteria
- D. Decomposer bacteria
4. A student finds that a compost heap releases carbon dioxide as it breaks down. Which process is directly responsible?
- A. Photosynthesis by bacteria
- B. Respiration by decomposers
- C. Combustion of the compost
- D. Nitrification
5. Nitrifying bacteria convert ammonium compounds into nitrates in two steps. What is the correct order?
- A. Nitrates then nitrites
- B. Nitrites then nitrates
- C. Nitrogen gas then nitrites
- D. Ammonia then nitrogen gas