Across
1
Unit of heredity
4
Mass per unit volume
6
Infectious microscopic agent
10
Magnetic metallic element
11
Icy body with a tail near the sun
Down
2
Tissue that contracts for movement
3
Compound containing oxygen
5
Group of similar cells
6
Gas form of a liquid
7
Center of an atom or cell
8
Solid with repeating atomic pattern
9
Our home planet