Across
1
Amplified beam of light
4
Basic unit of life
5
Absolute temperature scale unit
6
Blocking of light by a celestial body
8
Center of an atom or cell
10
Measure of matter in an object
Down
2
Tissue that contracts for movement
3
Substance with pH above 7
4
Element found in all living things
7
Mass per unit volume
9
Gas form of a liquid