Across
1
Biological catalyst
3
Precious yellow metallic element
4
Element found in all living things
5
Gas form of a liquid
8
Chemical element in table salt
9
Nerve cell in the brain
10
Smallest unit of an element
11
Unit of electric potential
Down
2
Tectonic landmass section
3
Unit of heredity
6
Center of an atom or cell
7
Tissue that contracts for movement
12
Molten rock beneath Earth surface