Science

3. The organ system that protects the body against infections.
4. The smallest functional unit of a living organism. It contains parts to carry out life processes.
5. An animal that is eaten by another animal.
7. Tissue found inside some bones where new blood cells are made.
8. The cell component that surrounds the cell and strengthens it. In plant cells it is made of cellulose.
9. An animal cell that transmits electrical impulses around the body.
12. Green plant or algae that makes its own food using sunlight by the process of photosynthesis.
14. An animal cell that transports oxygen around the body.
18. Living things made up of many types of cell.
19. Connect muscles to bones.
20. A measure of the number of particles in a given volume.
21. Parts of the skeleton where bones meet.

1. A particular place or role that an organism has in an ecosystem
2. The cell component that surrounds the cell and controls movement of substances in and out.
6. An animal that eats other animals.
10. The plant cell component that absorbs light so the plant can make food by photosynthesis.
11. Connect bones in joints.
13. A chemical reaction where food and oxygen are converted into water and carbon dioxide, enabling energy transfer.
15. A tissue that forms a hard structure, used to protect organs and used for movement.
16. The cell component containing genetic material
17. The area in which an organism lives.