Question 1: Which of the following is a primary producer in an ecosystem?

Answer: Plants

Question 2: True or False: Decomposers are essential for recycling nutrients in an ecosystem.

Answer: True

Question 3: Define 'food chain' and explain its importance in an ecosystem.

Answer: A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another. It is important because it illustrates the flow of energy and how organisms are interconnected.

Question 4: Which statement is true about energy flow in an ecosystem?

Answer: Energy decreases as it moves up the food chain.

Question 5: Match the following terms to their definitions:

Answer: See full answer key

Question 6: True or False: In a food web, each organism is part of only one food chain.

Answer: False

Question 7: Describe the role of herbivores in an ecosystem.

Answer: Herbivores are animals that consume plants for energy. They play a crucial role by transferring energy from producers to higher trophic levels.

Question 8: Calculate the energy transfer efficiency if a primary consumer receives 500 J from a producer that had 5000 J of energy. Use the formula: (Energy transferred/Energy available) x 100.

Answer: 10%

Question 9: Order the following stages of the nitrogen cycle correctly:

Answer: See full answer key

Question 10: Fill in the blank: An organism that can produce its own food using sunlight is called a __________.

Answer: producer

Question 11: Explain the impact of removing a top predator from an ecosystem. Discuss the consequences on the food chain and overall ecosystem balance.

Answer: Removing a top predator can lead to an increase in the population of herbivores or other prey, which can result in overgrazing or depletion of plant resources. This can cause a trophic cascade, impacting biodiversity and ecosystem stability, as well as eventual decline of the predator population's prey species.

Question 12: What is the primary function of decomposers in a food web?

Answer: Decomposers break down dead organisms and waste, recycling nutrients back into the ecosystem, which supports plant growth.

Question 13: Which of the following organisms is at the second trophic level?

Answer: Herbivores