▶️ Answer/Explanation
To identify a secondary consumer, we must trace the energy flow starting from the producer. In this web, alga is the producer. The organisms that eat the alga (stonefly, blackfly, and mayfly larvae) are primary consumers. A secondary consumer is an animal that eats these primary consumers.
Looking at the arrows, the diving beetle feeds directly on the stonefly, blackfly, and mayfly larvae. While the frog and stickleback can also be secondary consumers in certain chains, the diving beetle exclusively occupies that level in the paths shown from the larvae. Based on the provided marking key, choice B is the designated correct answer.
✅ Answer: (B)
▶️ Answer/Explanation
In a food chain diagram, the arrows represent the flow of energy. A producer is the starting point of energy flow, usually capturing energy from the sun. In this diagram, energy flows from organism C to organism B, and then to organism A, identifying C as the producer. Additionally, the arrows pointing from A, B, and C toward D indicate that D is likely a decomposer, receiving energy from all other levels when they die or produce waste. Since C is the only organism that provides energy to the consumers without receiving it from another organism in the chain, it must be the producer.
✅ Answer: (C)
✅ Answer: (C)
▶️ Answer/Explanation
To solve this, we must trace the arrows in the diagram from the producer (grass) to the top predators. Option (B) correctly follows a sequence of arrows present in the web: grass is eaten by the grasshopper, the grasshopper is eaten by the frog, and the frog is eaten by the hawk. Other options fail because they suggest connections that don’t exist; for example, there is no arrow from grass directly to a frog (A), no arrow from a grasshopper to a mouse (C), and no arrow from a rabbit to an owl (D). Therefore, only the second sequence represents a valid pathway for energy flow in this specific ecosystem.
✅ Answer: (B)
✅ Answer: (B)