Across
1
Second lightest element
3
Substance with pH above 7
4
Center of an atom or cell
5
Natural satellite of Earth
6
Icy body with a tail near the sun
Down
2
Group of similar cells
4
Nerve cell in the brain
7
Glass that splits light into spectrum
Second lightest element
Substance with pH above 7
Center of an atom or cell
Natural satellite of Earth
Icy body with a tail near the sun
Group of similar cells
Nerve cell in the brain
Glass that splits light into spectrum