Across
1
Molten rock beneath Earth surface
3
Positive particle in nucleus
4
Tissue that contracts for movement
7
Unit of power
9
Compound containing oxygen
11
The Red Planet
13
Nerve cell in the brain
Down
2
Element found in all living things
3
Tectonic landmass section
4
Measure of matter in an object
5
Smallest unit of an element
6
Mass per unit volume
8
Preserved remains of ancient life
10
Gas form of a liquid
12
Icy body with a tail near the sun