Across
1
Our home planet
4
Substance with pH below 7
5
Center of an atom or cell
6
Precious yellow metallic element
8
Molten rock beneath Earth surface
11
Hottest planet in solar system
Down
2
Amplified beam of light
3
Icy body with a tail near the sun
7
Unit of heredity
9
Substance with pH above 7
10
Basic unit of life