30. Interaction between two species as both attempt to use the same environmental resources is A. competition. B. a community. C. an ecosystem. D. predation. E. symbiosis. 31. A. competition. B. a community. C. an ecosystem. D. predation. E. symbiosis. Interaction between two species in which one feeds on the other is 32. A form of symbiosis in which one participant benefits and the other apparenty is not benefited nor harmed A. commensalism. B. parasitişn. C. mutualism. D. coevolution. E. symbiosis. 33. A small marine amphipod has recently been discovered that carries another bad tasting organism on its back against its normal behavior. The “backpack” organism tastes bad. If a fish ingests the pair, it immediately spits them back out. If the amphipod is alone, however, the amphipod is readily eaten and swallowed. There is no apparent benefit in this relationship for the “backpack” organism which appears to be neither helped nor harmed This is therefore a case of A. mutualism. B. parasitism. C. commensalism. D. competitive exclusion. E. predation 34. A form of symbiosis in which both participants benefit is A. commensalism. B. parasitism. C. mutualism. D. predation. E. competition. 35. The is made of a community of organisms plus its physical environment. A. food chain B. habitat C. niche D. ecosystem E. trophic level 36. An ecosystem consists of what two components? A grazing and detritus food chains B. habitat and niches C. biotic and abiotic factors D. trophic and eutrophic factors E. water and temperature 37. Which of the following is a biotic factor in an ecosystem? A. the food chain B. inorganic nutrients C. water availability D. temperature E. sunlight 38. Which sequence correctly illustrates the most plausible food chain? A. algae, insect larvae, fish, humans B. algae, fish, insect larvae, humans C. insect larvae, algae, fish, humans D. fish, insect larvae, algae, humans 39. In a certain ecosystem, caterpillars eat grass. Field mice eat the caterpillars and seeds from the grass. Snakes eat the mice. Hawks eat both the snakes and mice. Such an arrangement would be considered a(n) A. food web. B. food chain. C. ecosystem. D. first trophic level. E. second trophic level 40. In the following food chain, which organism is at the third trophic level? grass rabbits → snakes → hawks → foxes