Across
1
Tissue that contracts for movement
4
Unit of heredity
7
Amplified beam of light
8
Nerve cell in the brain
10
Disturbance that transfers energy
Down
2
Element found in all living things
3
Substance with pH above 7
5
Curved glass that refracts light
6
Icy body with a tail near the sun
8
Center of an atom or cell
9
Our home planet