Description This worksheet contains 100 comprehensive questions designed for high school students to explore the complex roles of organisms in ecosystems. Topics include producers, consumers, decomposers, ecosystem engineers, keystone species, biogeochemical cycles, human impacts, and symbiotic interactions. Students are asked to analyze the ecological significance of photosynthetic organisms, chemosynthetic bacteria, phytoplankton, herbivores, omnivores, predators, parasites, decomposers, and m