1. Which of the following are considered primary producers in an ecosystem?
A) Herbivores
B) Carnivores
C) Plants and algae
D) Decomposers
Answer: C) Plants and algae
2. What role do herbivores play in an ecosystem?
A) Producers
B) Primary consumers
C) Secondary consumers
D) Decomposers
Answer: B) Primary consumers
3. Which of these organisms is found at the tertiary trophic level?
A) Grass
B) Insects
C) Wolves
D) Bears
Answer: C) Wolves
4. Which of the following organisms are examples of decomposers?
A) Lions
B) Fungi and bacteria
C) Frogs
D) Grasshoppers
Answer: B) Fungi and bacteria
5. Which trophic level does a carnivore that eats herbivores belong to?
A) Primary producer
B) Primary consumer
C) Secondary consumer
D) Tertiary consumer
Answer: C) Secondary consumer
6. The energy transfer efficiency between trophic levels is typically:
A) 100%
B) 10%
C) 50%
D) 0%
Answer: B) 10%
7. Which of the following best describes the function of producers in a food chain?
A) They break down organic matter.
B) They obtain energy by consuming other organisms.
C) They produce energy through photosynthesis.
D) They recycle nutrients.
Answer: C) They produce energy through photosynthesis.
8. What is the main energy source for primary producers?
A) Chemical reactions
B) Solar energy
C) Organic matter
D) Other organisms
Answer: B) Solar energy
9. In a food chain, which level consumes both plants and animals?
A) Primary producer
B) Primary consumer
C) Omnivores
D) Decomposers
Answer: C) Omnivores
10. Which of the following is an example of a secondary consumer?
A) Grass
B) Grasshopper
C) Mouse
D) Snake
Answer: D) Snake
11. Decomposers in an ecosystem are responsible for:
A) Producing energy
B) Recycling nutrients
C) Consuming primary consumers
D) Consuming producers
Answer: B) Recycling nutrients
12. The organisms in which trophic level are also known as first-order consumers?
A) Producers
B) Herbivores
C) Carnivores
D) Omnivores
Answer: B) Herbivores
13. Which of these is the highest trophic level in a typical food chain?
A) Primary producer
B) Secondary consumer
C) Tertiary consumer
D) Decomposers
Answer: C) Tertiary consumer
14. A food web is different from a food chain because:
A) A food web represents multiple, interconnected food chains.
B) A food web is simpler than a food chain.
C) A food web is limited to one species.
D) A food web does not involve producers.
Answer: A) A food web represents multiple, interconnected food chains.
15. Which of the following is most likely to be at the top of a food chain?
A) A producer
B) A herbivore
C) A carnivore
D) A decomposer
Answer: C) A carnivore
16. Which of the following statements about trophic levels is true?
A) Energy increases as you move up trophic levels.
B) The number of organisms increases at each trophic level.
C) Producers make up the first trophic level.
D) Trophic levels are always in a linear sequence.
Answer: C) Producers make up the first trophic level.
17. Which of the following organisms is at the primary trophic level in most ecosystems?
A) Herbivores
B) Carnivores
C) Algae
D) Decomposers
Answer: C) Algae
18. Which of the following is the correct order of trophic levels in a typical food chain?
A) Primary consumer → Producer → Secondary consumer
B) Producer → Primary consumer → Secondary consumer
C) Secondary consumer → Producer → Primary consumer
D) Decomposer → Producer → Primary consumer
Answer: B) Producer → Primary consumer → Secondary consumer
19. Which of these organisms would likely be at the bottom of the food chain?
A) Rabbit
B) Grasshopper
C) Sunflower
D) Snake
Answer: C) Sunflower
20. The pyramid of energy illustrates that:
A) Energy is lost as you move up trophic levels.
B) The energy content increases at higher trophic levels.
C) Energy is conserved at each trophic level.
D) Energy is equally distributed at all trophic levels.
Answer: A) Energy is lost as you move up trophic levels.
21. Which type of organism is most commonly found at the second trophic level?
A) Primary producers
B) Herbivores
C) Carnivores
D) Decomposers
Answer: B) Herbivores
22. In a food chain, what is the role of secondary consumers?
A) They consume only producers.
B) They consume only herbivores.
C) They consume both producers and consumers.
D) They break down dead organisms.
Answer: B) They consume only herbivores.
23. What happens to the amount of energy available as you move up the trophic levels?
A) It increases
B) It remains the same
C) It decreases
D) It fluctuates
Answer: C) It decreases
24. Which group of organisms plays a key role in breaking down organic material in ecosystems?
A) Producers
B) Herbivores
C) Decomposers
D) Carnivores
Answer: C) Decomposers
25. Which of the following is true about primary consumers in most ecosystems?
A) They are herbivores.
B) They are carnivores.
C) They are decomposers.
D) They are producers.
Answer: A) They are herbivores.
26. Which trophic level includes organisms like fungi and bacteria?
A) Primary consumers
B) Decomposers
C) Secondary consumers
D) Tertiary consumers
Answer: B) Decomposers
27. Which level of a trophic pyramid would contain the largest biomass?
A) Producers
B) Herbivores
C) Carnivores
D) Decomposers
Answer: A) Producers
28. Which of the following is most likely to be a decomposer?
A) Fox
B) Fungi
C) Rabbit
D) Eagle
Answer: B) Fungi
29. What does a food web show that a food chain does not?
A) Energy flow in an ecosystem
B) How organisms interact in an ecosystem
C) The energy of primary consumers
D) The breakdown of organic matter
Answer: B) How organisms interact in an ecosystem
30. Which of these best describes a tertiary consumer?
A) A herbivore that eats plants.
B) An animal that eats only primary consumers.
C) A decomposer breaking down dead material.
D) A predator at the top of the food chain.
Answer: D) A predator at the top of the food chain.
