Biology: The Dynamics of Life

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instructions: Complete the crossword puzzle. Use the clues to help you solve the puzzle.

Across

1. level: organism that represents a feeding step in the movement of energy and materials through an ecosystem.

8. the total mass or weight of ail living matter in a given area. 10. web: model that shows all the possible feeding relationships at each trophic level in a

community. 12. symbiotic relationship in which one species benefits and the other species is neither harmed

nor benefited.

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Biology: The Dynamics of Life

16. interactions among populations in a community; the community's physical surroundings, or abiotic factors. •

17. group of organisms all of the same species, which interbreed and live in the same place at the same time.

19. scientific study of interactions between organisms and their environments. 20. permanent, close association between two or more organisms of different species.

Down 2. organisms that cannot make their own food and must feed on other organisms for energy and

nutrients. 3. place where an organism lives out its life. 4. symbiotic relationship in which one organism benefits at the expense of another, usually

another species. 5. community: a community made up of interacting populations in a certain area at a

certain time. 6. organisms that use energy from the sun or energy stored in chemical compounds to

manufacture their own nutrients. 7. portion of Earth that supports life; extends from high in the atmosphere to the bottom of the

oceans. 9. factors: all the living organisms that inhabit an environment.

11. organisms, such as fungi and bacteria, that break down and absorb nutrients from dead ^ organisms.

13. a symbiotic relationship in which both species benefit. 14. role or position a species has in its environment; includes all biotic and abiotic interactions as

an animal meets its needs for survival and reproduction. 15. factors: nonliving parts of an organism's environment, air currents, temperature,

moisture, light, and soil are examples. 18. chain: simple model that shows how matter and energy move through an ecosystem.

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