Across
1
Path of a planet around the sun
4
Group of similar cells
5
Smallest unit of an element
8
Hottest planet in solar system
9
Substance with pH below 7
10
Unit of heredity
12
Second lightest element
Down
2
Tectonic landmass section
3
Infectious microscopic agent
6
Push or pull on an object
7
Blocking of light by a celestial body
11
Preserved remains of ancient life
13
Substance with pH above 7
14
Fourth state of matter