Across
1
Preserved remains of ancient life
4
Solid with repeating atomic pattern
6
Nerve cell in the brain
7
Chemical element in table salt
11
Measure of matter in an object
12
Icy body with a tail near the sun
13
Tectonic landmass section
Down
2
Tissue that contracts for movement
3
Mass per unit volume
5
Push or pull on an object
8
Center of an atom or cell
9
Group of similar cells
10
Unit of force