Across
1
Ball of burning gas in space
4
Naturally occurring inorganic solid
7
Nerve cell in the brain
9
Unit of electric potential
10
Unit of energy
12
Fourth state of matter
Down
2
Tissue that contracts for movement
3
Measure of matter in an object
5
Unit of heredity
6
Element found in all living things
8
Solid with repeating atomic pattern
11
Mass per unit volume