Across
- 2. the air-- various gases-- that surround the earth
- 3. Any of a class of nitrogen-containing organic compounds that come from plants and have an effect on the body. Common alkaloids include caffeine, nicotine, and codeine.
- 6. so small it can only be seen with a microscope
- 7. the science of the earth and its structures and composition
- 10. the science that studies the basic laws of the physical universe: matter, energy, and the ways they interact
- 11. Method A scientific process of investigation and discovery involving a variety of techniques such as systematic observation, description, measurement, experimentation, modeling and the formulation, testing, and modification of hypotheses.
- 15. anything with substance (mass) that occupies space
- 17. the production of carbohydrates from sunlight and water
- 19. the ability to do work
- 21. the science of chemical reactions
- 22. the study of the stars and universe
- 23. the study of life
- 25. a test to learn what will happen under specific, controlled conditions, designed to prove or disprove a hypothesis
Down
- 1. an idea about how something works or how to solve a problem that can be tested to confirm or disprove it
- 4. the smallest unit of an element, made up of one or more protons, an equal number of electrons, and possibly one or more neutrons
- 5. combinations of atoms that are the building blocks of matter
- 8. A temperature scale with its units in Kelvin. A temperature in degrees Celsius can be converted to Kelvin by adding 273.15 to its value.
- 9. animals with backbones
- 12. long-term weather conditions usually in a region
- 13. the specific environmental conditions that are home to a species—where it belongs
- 14. breathing; the process of taking in oxygen and releasing carbon dioxide
- 16. the science of the relationships of living things to their environment and each other
- 18. related to the sun
- 20. an animal that eats plants
- 24. Number The number of protons in an atomic nucleus.