Across
1
Infectious microscopic agent
4
Icy body with a tail near the sun
5
Basic unit of life
8
Tectonic landmass section
11
The Red Planet
Down
2
Force that attracts objects together
3
Preserved remains of ancient life
5
Element found in all living things
6
Natural satellite of Earth
7
Amplified beam of light
9
Disturbance that transfers energy
10
Curved glass that refracts light