Across
1
Group of similar cells
3
Biological catalyst
7
Molten rock beneath Earth surface
9
Push or pull on an object
10
Curved glass that refracts light
11
Chemical element in table salt
13
Mass per unit volume
Down
2
Unit of heredity
4
Smallest unit of an element
5
Second lightest element
6
Infectious microscopic agent
8
Nerve cell in the brain
12
The Red Planet
14
Precious yellow metallic element