Across
- 4. group of organisms
- 5. acts as fuel
- 6. arranged in an orderly way
- 9. natural changes that occur during life
- 10. individual life form
- 13. inherited characteristic
Down
- 1. reaction to a stimulus
- 2. study of living organisms
- 3. conditions in which living things operate
- 7. production of offspring
- 8. internal conditions to maintain life
- 11. addition of mass to an organism
- 12. event that evokes a specific function in an organ or tissue