Across
1
Center of an atom or cell
4
Naturally occurring inorganic solid
5
Ball of burning gas in space
6
Infectious microscopic agent
7
Disturbance that transfers energy
Down
2
Unit of electric potential
3
Hottest planet in solar system
4
Measure of matter in an object
8
Group of similar cells
9
Force that attracts objects together
10
Preserved remains of ancient life
11
Glass that splits light into spectrum