Our Environment: Ecosystems, Food Chains & Energy Transfer

Grade 9 Science — Our Environment: Ecosystems, Food Chains & Energy Transfer: 25 practice questions with instant scoring and explanations.

1. Which of the following is a biotic component of an ecosystem?
2. In a food chain, producers are:
3. What is the role of decomposers in an ecosystem?
4. In the food chain: Grass → Rabbit → Fox, the rabbit is a:
5. Which trophic level has the most energy in an ecosystem?
6. According to the 10% energy rule, if producers store 10,000 J of energy, primary consumers obtain:
7. A food web differs from a food chain because it:
8. Which organisms are at the bottom of every food chain?
9. The progressive accumulation of substances in organisms at higher trophic levels is called:
10. If pesticide concentration in plants is 1 ppm, what will be its approximate concentration in herbivores?
11. Abiotic factors in an aquatic ecosystem include:
12. In a terrestrial ecosystem, which is the ultimate source of energy?
13. Energy transfer between trophic levels is:
14. Which of the following animals is a secondary consumer?
15. Parasitic relationships in an ecosystem:
16. The concentration of harmful chemicals increases as you move up the food chain. This is because:
17. If a food chain has 5 trophic levels and producers have 100,000 J, how much energy reaches the tertiary consumers?
18. Nitrogen cycle involves:
19. An organism that can produce its own food is called a:
20. In an ecosystem, if all herbivores were suddenly removed, which would happen first?
21. Biological magnification is most problematic with:
22. The pyramid of numbers in an ecosystem typically shows:
23. A symbiotic relationship where both organisms benefit is called:
24. Which of the following is an abiotic factor?
25. The percentage of energy transferred from one trophic level to the next is approximately: