7. Which of the following doesn’t belong to the group?

A. plants

B. soil

C. water

D. wind

8. Which of the following organisms is classified as scavenger?

A. ants

B. beetles

C. termite

D. vulture

9. What term is applied to the role an organism plays in its habitat?

A. niche

B. symbiosis

C. abiotic factor

D. biotic factor

10. Ants guide aphids to fresh leaves for feeding. What kind of relationship exists

between these organisms?

A. competition

C. mutualism

B. cooperation

D. predation

11. Which of the following will receive the least amount of energy in food chain?

A. first-level consumer

C. second-level consumer

B. third-level consumer

D. fourth-order consumer

12. Which pair of organisms exhibits predation?

A. dog and tick

C. whale and barnacles

B. sharks and sea lion

D. ocean sunfish and its parasites

13. Which two terms both apply to organisms that make their own food? .

A. humus and detritus

C. autotrophs and heterotrophs

B. predator and parasite

D. photosynthetic and chemosynthetic

14. Which of the abiotic factors serves as the ultimate source of energy utilized by

photosynthetic organisms?

A. nitrogen

B. oxygen

C. sunlight

D. water

15. Why are decomposers essential in ecosystems? Decomposers __________________.

A. bring back the nutrients present in the soil

B. keep the population of other species in check

C. supply the ecosystem with the needed energy

D. utilize energy and nutrients for the direct benefit of other organisms
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