Answer: Removal causes disproportionately large effects on the ecosystem.
- A Possess the single largest overall biomass within the ecosystem
- B Removal causes disproportionately large effects on the ecosystem
- C Maintain the single largest population size in the community
- D Occupy the single smallest geographic range in the habitat
Correct answer: B. Removal causes disproportionately large effects on the ecosystem
Explanation: Keystone species have a disproportionate impact on ecosystem structure relative to their biomass. Removing them causes ecosystem collapse (e.g., sea otters, wolves).
Energy pyramid showing a simple food chain (producer to herbivore to carnivore) with energy decreasing roughly tenfold at each trophic level.
Concept context
Ecosystems, food chains, energy flow, nutrient cycles, biodiversity, and conservation.