Across
- 3. A negatively charged particle orbiting an atom's nucleus.
- 7. A tiny infectious agent that replicates inside cells.
- 8. An instrument for viewing distant objects in space.
- 9. The branch of science concerned with matter and energy.
- 10. A gas essential for human life.
- 12. A massive system of stars, dust, and gas held by gravity.
- 13. The study of Earth's structure and substances.
- 14. A substance consisting of only one type of atom.
Down
- 1. A group of similar organisms that can breed.
- 2. The variety of life in an ecosystem.
- 4. A tool used to see tiny objects.
- 5. A change in a DNA sequence.
- 6. A substance that provides immunity to disease.
- 11. The average weather conditions of a region.