Across
1
Unit of force
5
Group of similar cells
6
Push or pull on an object
7
Naturally occurring inorganic solid
8
Smallest unit of an element
12
Blocking of light by a celestial body
Down
2
Unit of heredity
3
Gas essential for breathing
4
Path of a planet around the sun
9
Basic unit of life
10
Absolute temperature scale unit
11
The Red Planet