Across
1
Unit of heredity
4
Reddish electrical conductor
6
Curved glass that refracts light
8
Force that attracts objects together
9
Icy body with a tail near the sun
11
Center of an atom or cell
Down
2
Magnetic metallic element
3
Biological catalyst
5
Particle of light
7
Tissue that contracts for movement
10
Ball of burning gas in space