Across
- 1. The gaseous layer surrounding the Earth
- 3. All the water on Earth, including oceans, rivers, and lakes
- 4. A well-substantiated explanation of an aspect of the natural world
- 8. All regions of Earth that support life
- 12. The movement of the Earth’s plates that can cause earthquakes and volcanoes
- 14. A variable that is changed by the independent variable
- 17. The group that does not receive the experimental treatment and is used for comparison
- 18. The water in all its forms, including glaciers and ice caps
Down
- 2. Large areas characterized by climate and plant life on land
- 5. An educated guess that can be tested through experimentation
- 6. A variable that is changed or controlled to observe its effect
- 7. Cycles related to non-living components of ecosystems, like water and nutrients
- 9. A tool used to identify organisms based on a series of choices
- 10. A conclusion drawn based on evidence and reasoning
- 11. Species that are non native, spread rapidly and cause harm to new environments
- 13. The solid part of the Earth, including rocks and minerals
- 15. The complete disappearance of a species from the Earth
- 16. Variables that are kept the same to ensure a fair test