Year 8 Crossword

1. - the process where humans select which organisms to reproduce together based on their desirable traits (selective ______________)
4. - things that make a species well suited to its environment
8. - the differences between individuals in a species
9. - the layer of the Earth where metals are found
10. - a sign of a chemical reaction
11. - a type of variation where the characteristic is placed in a category
13. - a sign of a chemical reaction (________________ change)
15. - a sign of a chemical reaction (__________ change)
17. - you can tell which metals are most reactive by placing them in water or _______
18. - organisms that can reproduce to make fertile offspring are said to be in the same ___________
20. - the word we use to describe the fact that metals can be stretched into wires
21. - metals are good heat and electrical _____________
22. - the list of metals in order of their reactivity (the reactivity ____________)
23. - a property of metals (to do with their appearance)

2. - the process where organisms adapt over millions of years to better suit their environment
3. - the word we use to describe the fact that metals can be reshaped without being broken.
5. - a type of variation between different species
6. - an unreactive metal that is found in its pure 'native' form in the ground
7. - the name for rocks that contain lots of metals
12. - a type of variation within a species
14. - metals can be placed in order of how _____________ they are
15. - a type of variation where the characteristic can be measured
16. - evolution can be summarised as survival of the _______________
19. - a type of reaction where a more reactive metal takes the place of a less reactive metal in a compound