Across
1
Absolute temperature scale unit
4
Path of a planet around the sun
7
Center of an atom or cell
8
Basic unit of life
11
Molten rock beneath Earth surface
12
Curved glass that refracts light
13
The Red Planet
Down
2
Particle of light
3
Preserved remains of ancient life
5
Mass per unit volume
6
Unit of electric potential
9
Reddish electrical conductor
10
Substance with pH above 7
14
Biological catalyst