Across
- 4. believed on the principle that physical changes in organisms during their lifetime
- 6. heve bones
- 8. is the center of the Solar System
- 10. is the father of Evolution
Down
- 1. are the basic building blocks of all living things.
- 2. are vertebrates. The females produce milk
- 3. is the unique planet that has water
- 5. is the smallest planet in the Solar System
- 7. circulates through our body
- 9. is the second planet from the Sun