Across
- 1. substance that forms by joining many small molecules
- 9. long chain of amino acid molecules
- 12. network of threadlike proteins inside a cell
- 14. one or more sugar molecules
- 15. living things are made of one or more cells
- 16. membrane-bound cell structure with a specialized function
Down
- 2. membrane-bound organelle that uses light energy and makes food
- 3. purpose for which something is used
- 4. protects the inside of a cell from the environment
- 5. fluid inside cell that contains salts and other molecules
- 6. macromolecule that forms when a long chain of nucleotides join togther
- 7. outer covering
- 8. stiff stucture outside the cell membrane
- 10. large macromolecule that does not dissolve in water
- 11. directs all cell activities and contains DNA
- 13. explanation based on scientific knowledge resulting from several observations and experiments