Across
1
Biological catalyst
4
Chemical element in table salt
5
Molten rock beneath Earth surface
7
Force that attracts objects together
8
Particle of light
10
Blocking of light by a celestial body
11
Tissue that contracts for movement
Down
2
Compound containing oxygen
3
Amplified beam of light
6
Center of an atom or cell
8
Fourth state of matter
9
Smallest unit of an element