Across
1
Natural satellite of Earth
3
Tissue that contracts for movement
4
Basic unit of life
5
Blocking of light by a celestial body
10
Gas form of a liquid
11
Absolute temperature scale unit
12
Substance with pH above 7
Down
2
Preserved remains of ancient life
3
Naturally occurring inorganic solid
6
Nerve cell in the brain
7
Biological catalyst
8
Unit of energy
9
The Red Planet
13
Disturbance that transfers energy