Across
1
Force that attracts objects together
2
Particle of light
4
Tissue that contracts for movement
5
Push or pull on an object
6
Unit of force
12
Gas form of a liquid
Down
2
Fourth state of matter
3
Gas essential for breathing
7
Reddish electrical conductor
8
Disturbance that transfers energy
9
Precious yellow metallic element
10
Unit of heredity
11
Curved glass that refracts light
13
Element found in all living things