Across
1
Infectious microscopic agent
4
Element found in all living things
5
Nerve cell in the brain
7
Fourth state of matter
11
Substance with pH above 7
Down
2
Path of a planet around the sun
3
Curved glass that refracts light
6
Molten rock beneath Earth surface
8
Absolute temperature scale unit
9
Blocking of light by a celestial body
10
Substance with pH below 7