Across
- 5. a chemical made by some cells to change how other cells work
- 6. kill pests
- 7. small bones in the back
- 8. studies plants
- 9. break down manure and release mineral salts from it
- 13. chemical reaction that happens in all living cells
- 14. a behaviour learned within a few hours after the birth
- 15. where photosynthesis occurs
Down
- 1. thousands of different substances
- 2. an alloy of copper and zinc
- 3. the seed starts to grow
- 4. 46 of them in your body
- 10. scientist who study insects
- 11. shaped to reduce air resistance
- 12. part of the rib cage