Final Crossword

3. a salt or ester of phosphoric acid
6. cover body surfaces, line body cavities, and hollow organs; provide many functions but mainly protection
10. makes own food from sunlight
11. any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents
13. chemical fuel for living things
14. To regulate all body functions
15. protects and supports the body
16. Any relationship in which two species live closely together
18. Amount of living tissue within a trophic level
19. Particles move from high to low concentration
23. Soil bacteria converts nitrates into nitrogen gas
24. a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction

1. in take of liquids
2. All organisms in an area plus the nonliving environment
4. the state of steady internal, physical, and chemical conditions; it helps maintain stability
5. basic unit of life
7. use light energy to make two molecules needed for the next stage of photosynthesis
8. forcing materials out
9. the first step of cellular respiration and anaerobic respiration
12. a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change
14. gets rid of waste
17. Diffusion of water through a semipermeable membrane
20. Atoms of the same element with different numbers of neutrons
21. an organism's occupation within its habitat which is composed of both Biotic and Abiotic factors
22. a substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together