Across
1
Gas essential for breathing
3
Glass that splits light into spectrum
4
Curved glass that refracts light
7
Preserved remains of ancient life
8
Absolute temperature scale unit
11
Ball of burning gas in space
Down
2
Force that attracts objects together
4
Amplified beam of light
5
Infectious microscopic agent
6
Nerve cell in the brain
9
Unit of heredity
10
Chemical element in table salt