Across
1
Naturally occurring inorganic solid
4
Group of similar cells
6
Curved glass that refracts light
7
Gas form of a liquid
Down
2
Mass per unit volume
3
Nerve cell in the brain
5
Preserved remains of ancient life
8
Chemical element in table salt
9
Our home planet
10
Substance with pH below 7
11
Measure of matter in an object