Across
1
Second lightest element
5
Tissue that contracts for movement
6
Our home planet
7
Element found in all living things
9
Solid with repeating atomic pattern
12
Particle of light
Down
2
Icy body with a tail near the sun
3
Fourth state of matter
4
Naturally occurring inorganic solid
8
Ball of burning gas in space
10
Nerve cell in the brain
11
Biological catalyst
13
Tectonic landmass section