1
							2
						3
												4
									5																6
							7
							8
						9												10
								11
	12																							13
																		14
				15
	16
			17									18		19												20
											21
22																	23
																							24
					25															26
										27
					28
																29

Across 2. Process in which nitrogen gas is captured and converted into a form plants use (2 Words) 3. Factor being measured in a controlled experiment; changes with changes of the independent variable (2 Words) 4. Heterotroph that decomposes organic material and returns the nutrients to soil, air, and water 7. A series of problem-solving procedures (observations, forming hypotheses, experimenting, gathering and analyzing data, and drawing conclusions) (2 Words) 8. Organism that cannot make its own food and gets its nutrients and energy requirements by feeding on other organisms 10. Symbiotic relationship in which both organisms benefit 11. Symbiotic relationship in which one organism benefits at the expense of another organism 12. Scientific study of all the interrelationships between organisms and their environment 14. Act of one organism feeding on another organism 15. In a controlled experiment, the group not receiving the factor being tested (2 Words) 19. Assumption based on prior experience 21. A statement that describes a natural phenomenon that are proven by data 22. Regulation of an organism's internal environment to maintain conditions needed for life 25. Group of organisms of the same species that occupy the same geographic place at the same time 26. Physical area in which an organism lives 27. Simplified model that shows a single path for energy flow through an ecosystem (2 Words) 28. Biological community and all the nonliving factors that affect it 29. Any change in an organism's internal or external environment that causes the organism to react

Down 1. The one factor that can be changed in a controlled experiment; factor that affects outcome (2 Words) 5. Any living factor in an organism's environment (2 Words) 6. Organism's reaction to a stimulus 9. Orderly structure shown by living things 13. Science of life; how living things interact, systems function, and how they function at a molecular level 16. Testable explanation of a situation 17. Procedures in an experiment may be repeated and the results are evaluated by scientists who are in the same field or conducting similar research (2 Words) 18. Heterotroph that preys on other heterotrophs 20. Process that results in mass being added to an organism 23. Chemical substance that living organisms obtain from the environment to carry out life processes and sustain life 24. Total mass of living matter at each trophic level