Across
1
Unit of heredity
2
Particle of light
4
Basic unit of life
5
Preserved remains of ancient life
10
Blocking of light by a celestial body
11
Absolute temperature scale unit
12
Force that attracts objects together
Down
2
Tectonic landmass section
3
Curved glass that refracts light
5
Push or pull on an object
6
Reddish electrical conductor
7
Element found in all living things
8
Ball of burning gas in space
9
Biological catalyst