Across
1
Second lightest element
3
Precious yellow metallic element
6
Group of similar cells
7
Blocking of light by a celestial body
13
Push or pull on an object
Down
2
Amplified beam of light
4
Compound containing oxygen
5
Gas essential for breathing
8
Tectonic landmass section
9
Biological catalyst
10
Center of an atom or cell
11
Fourth state of matter
12
Basic unit of life