Across
1
Blocking of light by a celestial body
4
Tectonic landmass section
5
Unit of power
7
Hottest planet in solar system
8
Unit of heredity
10
Element found in all living things
11
Unit of electric potential
13
Positive particle in nucleus
Down
2
Icy body with a tail near the sun
3
Compound containing oxygen
4
Glass that splits light into spectrum
6
Group of similar cells
7
Infectious microscopic agent
9
Basic unit of life
12
Gas essential for breathing