Across
- 2. a simple sugar
- 4. something that someone or something needs
- 7. a very small amount of matter
- 10. process by which a green plant uses the sun's energy to make food
- 11. tiny living organisms
- 13. having to do with veins and vessels that carry fluids throughout an organism
- 14. the green substance in plants
Down
- 1. part of plant where photosynthesis takes place
- 3. a substance that gives color to plants and animals
- 5. very important or necessary for a job to be completed
- 6. taking in oxygen
- 8. a community of organisms and their physical environment
- 9. absolutely necessary
- 12. related to one or more cells