Across
1
Push or pull on an object
3
The Red Planet
4
Center of an atom or cell
5
Magnetic metallic element
6
Positive particle in nucleus
7
Chemical element in table salt
8
Smallest unit of an element
Down
1
Preserved remains of ancient life
2
Naturally occurring inorganic solid
3
Tissue that contracts for movement
4
Nerve cell in the brain
9
Unit of power